Welcome to the world of the Chemistry Merit Badge! Ever wondered why baking soda erupts into bubbles when vinegar is added? Or how the same carbon forms both charcoal and diamonds?
Chemistry unravels these mysteries and more by studying the substances that shape our world and universe. It helps us understand how substances interact and transform, how invisible forces connect molecules, and how these molecules are constructed.
The art of chemistry lies in imagining these unseen molecules and confirming their existence through science. As you delve into this journey, you’ll realize that chemistry isn’t just a subject, it’s a fascinating lens to view and understand the world. So gear up, future chemists, to discover a realm where everyday phenomena meet scientific explanation!
Chemistry Merit Badge Requirements
| 1. Do EACH of the following: (a) Describe three examples of safety equipment used in a chemistry laboratory and the reason each one is used. (b) Describe what a safety data sheet (SDS) is and tell why it is used. (c) Obtain an SDS for both a paint and an insecticide. Compare and discuss the toxicity, disposal, and safe-handling sections for these two common household products. (d) Discuss the safe storage of chemicals. How does the safe storage of chemicals apply to your home, your school, your community, and the environment? |
| 2. Do EACH of the following: (a) Predict what would happen if you placed an iron nail in a copper sulfate solution. Then, put an iron nail in a copper sulfate solution. Describe your observations and make a conclusion based on your observations. Compare your prediction and original conclusion with what actually happened. Write the formula for the reaction that you described. (b) Demonstrate how you would separate sand (or gravel) from water. Describe how you would separate table salt from water, oil from water, and gasoline from motor oil. Name the practical processes that require these kinds of separations and how the processes may differ. (c) Describe the difference between a chemical reaction and a physical change. |
| 3. Construct a Cartesian diver. Describe its function in terms of how gases in general behave under different pressures and different temperatures. Describe how the behavior of gases affects a backpacker at high altitudes and a scuba diver underwater. |
| 4. Do EACH of the following: (a) Cut a round onion into small chunks. Separate the onion chunks into three equal portions. Leave the first portion raw. Cook the second portion of the onion chunks until the pieces are translucent. Cook the third portion until the onions are caramelized, or brown in color. Taste each type of onion. Describe the taste of raw onion versus partially cooked onion versus caramelized onion. Explain what happens to molecules in the onion during the cooking process. (b) Describe the chemical similarities and differences between toothpaste and an abrasive household cleanser. Explain how the end use or purpose of a product affects its chemical formulation. (c) In a clear container, mix a half-cup of water with a tablespoon of oil. Explain why the oil and water do not mix. Find a substance that will help the two combine, and add it to the mixture. Describe what happened, and explain how that substance worked to combine the oil and water. |
| 5. List the five classical divisions of chemistry. Briefly describe each one, and tell how it applies to your everyday life. |
| 6. Do EACH of the following: (a) Name two government agencies that are responsible for tracking the use of chemicals for commercial or industrial use. Pick one agency and briefly describe its responsibilities to the public and the environment. (b) Define pollution. Explain the chemical impacts on the ozone layer and global climate change. (c) Using reasons from chemistry, describe the effect on the environment of ONE of the following: (1) The production of aluminum cans (2) Burning fossil fuels (3) Single-use items, such as water bottles, bags, straws, or paper. (d) Briefly describe the purpose of phosphates in fertilizer and in laundry detergent. Explain how the use of phosphates in fertilizers affects the environment. Explain why phosphates have been removed from laundry detergents. |
| 7. Do ONE of the following activities: (a) Visit a laboratory and talk to a chemist. Ask what that chemist does and what training and education are needed to work as a chemist. (b) Using resources found at the library and in periodicals, books, and the Internet (with your parent’s permission), learn about two different kinds of work done by chemists, chemical engineers, chemical technicians, or industrial chemists. For each of the four positions, find out the education and training requirements. (c) Visit an industrial plant that makes chemical products or uses chemical processes and describe the processes used. What, if any, by-products are produced and how are they handled? (d) Visit a county farm agency or similar governmental agency and learn how chemistry is used to meet the needs of agriculture in your county. |
Chemistry and Chemicals
Chemistry is one of the physical sciences. Science is the study by which people try to understand and explain our world and the universe in a rational, logical manner.
Chemistry is sometimes called the central science because its properties are important to biologists, physicists, geologists, and astronomers alike Chemistry is present throughout modern society in medicine, manufacturing, and agriculture.
1. What Is Chemistry?
Chemistry is the science of the study of matter. The matter is any. that has ma and space. Chemistry includes the study of substances, their structures, properties, and reactions, and the energy changes of those reactions.
Chemicals are made of molecules, and molecules are made of actors, Look at the water. It is a chemical, A water molecule is two hydrogen atoms attached to one oxygen atom.
Chemicals are considered pure substances because they are made up of only one type of substance. Often we encounter mixtures of several chemicals, Milk, for example, is mostly water.
Yet, milk also contains other chemicals such as calcium, fats, proteins, carbohydrates, vitamins, and minerals.
You can pick up the container of any commercial food or household product-like cereal, deodorant, or vitamins-and read the list of ingredients. All these ingredients are chemicals. Even the bottle and label are chemicals.
2. Compounds
When writing chemical formulas, chemists show the number of each type of atom in the compound. For example, the molecular formula of methane is CH, which means that there are four hydrogens (H) atoms and one carbon (C) atom in each molecule of methane.
A structural formula shows how these atoms are arranged.
Often, chemists need to know how to draw the structures of compounds. By knowing the structures, they can then understand many of the properties of the compounds.
Some molecules are very simple, containing only a few atoms. The air we breathe contains oxygen (O2), nitrogen (N). and carbon dioxide (CO2), along with other gases.
Other molecules are more complicated. Some contain dozens of atoms, while others contain hundreds or even millions of atoms. Table sugar is sucrose (C12H2011).
The deoxyribonucleic acid (DNA) within our cells that contains our genetic code is composed of only carbon, hydrogen, nitrogen, oxygen, and phosphorus, but it contains millions of these atoms in specific combinations.
3. What Are Chemicals?
When people hear the word chemicals, they may feel afraid. They unconsciously may think that all chemicals are poisonous, but not all chemicals are even dangerous. Remember that water (HO) is a chemical.
Everything in your house is made from chemicals, including the food you eat and the clothes you wear. Even your body is made of chemicals. To live and breathe, you must continuously carry out many chemical reactions within your body.
You eat complex molecules of carbohydrates, fats, and proteins. Your body uses these molecules for energy and to make new biomolecules for tissues such as muscle, hair, and nails.
4. Chemical Reaction
In a chemical reaction, the atoms in a molecule are combined or rearranged with atoms in another molecule to form a new compound that has different physical and chemical properties.
Combustion is one way to tell if a chemical change has taken place Try this experiment with the flame-one sign of chemical change. Look for another clue of a chemical change.
| Step 1 – Put on safety goggles. Stand a short candle (2 or 3 inches tall) n a bowl, with water about a half-inch deep. You may attach the clay to the candle and bowl to help keep the candle upright. Light the candle. Hold a cold. dry glass cup (not plastic) upside down over the burning candle. Does moisture collect on the inside of the glass! |
| Step 2 – Set the glass upside down over the candle. Note how and when the level of the water in the glass rises. Does the water now occupy about one-fifth of the volume of the glass? |
What Happened?
The three things necessary for combustion to occur are heat, fuel, and oxygen. Dry air is about 21 percent oxygen and 78 percent nitrogen by volume, with small amounts of other gases such as carbon dioxide and hydrogen.
The flame in this experiment actually goes out before all the oxygen is consumed, while the heat of the flame causes the gases to expand.
When the flame goes out, the temperature in the glass drops, causing the gases to contract and the water level to rise quickly. What is left in the glass is mostly nitrogen.
Chemists use equations to show the reactant and product molecules. Candle wax is often a variety of waxes with long chains of carbons and hydrogens. An equation for the combustion of hexamine, a common wax, is:
Reactants to Products
C6H12N4 + 602 + 3CO2 + 6H2O + 2N2 + heat
5. Physical Change
Ice melting and water evaporating are examples of physical change. In contrast to chemical reactions, physical change does not form new compounds.
Water is still H2O whether it is a liquid, solid, or gas. The change from one state to another does not change water’s molecular structure.
Every spring, a physical change occurs naturally when solid ice on mountaintops melts, flows as water downhill and evaporates to water vapor. This can be represented by the equation
H2O (S) -> H2O (l) -> H20 (g)
Solid -> Liquid -> Gas
Dry ice is frozen carbon dioxide. At room temperature, it changes directly from a solid to a gas. The surface temperature of dry ice is very cool at -109 degrees Fahrenheit.
Find an adult to help you with this experiment. Warn people in your area that this experiment will be noisy.
| Step 1 – Put on safety goggles to protect your eyes. |
| Step 2 – Fill a bowl with ice water and pour 1/4 cup water into an empty aluminum soda can. The smaller the opening in the top of the can, the better. |
| Step 3 – Put on oven mitts, then set the can on a stove burner. Turn the burner on high. Once steam begins to rise from the can, heat it for three more minutes. Caution: Keep your hands away from the hot steam! |
| Step 4 – Turn off the heat. Wearing oven mitts and using tongs, quickly remove the can. turn it upside down, and submerge it in the ice water |
What Happened?
The volume of a liquid expands by a factor of more than 1.000 when it becomes a gas. Imagine the steam inside the can pushing out the air molecules as it starts to boil.
The molecules of steam in their high-energy state spread out. with most escaping out of the top of the can.
When the can is inverted in the ice water, the water vapor becomes trapped in the can. The ice water quickly cools the can and the steam inside.
The gas steam contracts by a factor of more than 1,000 when it liquefies. Suddenly, the pressure inside the can drops and the can implodes. Bang!
Also Read: Geology Merit Badge
Safety and Chemistry
Some chemicals are safe enough to be eaten- such as sugar, cooking oil, and baking soda Other chemicals are so potentially dangerous that you need to wear gloves and safety goggles when you handle them.
Examples of dangerous chemicals are bathroom cleaners, drain cleaners. and acids. Many chemicals must be stored safely to avoid possible fires or poisonings. Flammable materials should be stored away from heat and flame, which are sources of ignition.
1. Storage in Your Home
If you have younger brothers and sisters, make sure your parents place child-proof locking devices on kitchen and bathroom cabinets. Before storing a chemical at home, read the label.
If the label recommends keeping it out of reach of children, store the chemical in a high or locked cabinet. Chemicals such as drain cleaners and bleach have warning labels.
2. Storage in Your School
At most schools, all chemicals are stored in a common area, often organized by hazard classification. Schools try to select less-toxic chemicals and minimize chemical use to reduce waste and safety risks.
Teachers working with chemicals receive training in safe storage, proper use, potential hazards, and disposal. Schools have a chemical spill plan in case of an accident.
3. Storage in Your Community
Businesses in your community use chemicals that can be toxic if not stored or used correctly.
A spilled chemical on business property could be washed by rain into a local stream, which could drain into a town’s water supply. The government regulates the proper use, storage, and disposal of chemicals.
4. Material Safety Data Sheet
What would you do if you accidentally splattered a chemical in your eyes! You should read the container’s label and follow the instructions. The label might tell you to rinse your eyes thoroughly and seek medical attention.
In the hospital’s emergency room, the nurse would ask what you splattered in your eyes. A bug killer called Bug-B-Dead might be all you knew. The nurse would know the chemicals were pesticides, but which one? A material safety data sheet is important in these situations.
By U.S. law, all chemical manufacturers and importers of hazardous substances-like pesticides, household cleaners, or even paint-must write an MSDS to tell users about potential hazards.
An MSDS gives both consumers and emergency personnel the correct procedures for using a particular substance.
A government agency called the Occupational Safety and Health Administration monitors exposure to chemicals in the workplace and MSDS reporting.
An MSDS allows the hazardous chemical manufacturer to alert the chemical user and emergency personnel about important safety information. Although formats can differ, U.S. law requires an MSDS to include certain data.
With your parent’s permission, find MSDS reports on paint and an insecticide. On both MSDS reports, look for the following information:
- Toxicity and health effects – both immediate upon exposure and long-term exposure effects.
- First aid – what to do if the product gets in a person’s eyes or on the skin, or is breathed into the lungs or swallowed.
- Reactivity if the substance will react with itself or other products, and the chemicals are released if the product is burned.
- Storage temperature, location, and handling to minimize risk.
- Disposal directions and legal limitations.
- Protective equipment-safety equipment for personal protection.
- Spill and leak procedures or actions to take in the event of a spill or leak.
- Physical data-for example, its melting point, boiling point, flash point, and flammability (if it will burn)
A material safety data sheet (MSDS) will contain several sections, all required by U.S. law. Eight sections are now required on an MSDS, though some internationally formatted material safety data sheets will have 16 sections,
The eight required sections are, with descriptions:
Section 1: The identity of the material and the manufacturer’s name, address, and emergency phone contact information.
Section 2: Hazard Ingredients. This section lists all of the hazardous ingredients in the product, as well as some of the exposure limits.
Section 3: Physical and Chemical Characteristics. This section tells what the product will look like, smell like, and also how it will react.
Section 4: Fire and Explosion Hazard Data. This section lists the flashpoints, firefighting materials/methods, and any unusual burning characteristics of the product.
Section 5: Reactivity. This section tells what and how other chemicals will react with the product.
Section 6: Health Hazard Data. This section lists any known routes of entry into the human body, as well as the associated health risks from each route of entry. It also lists any known cancer research that may have been done on the product.
Section 7: Precautions for Safe Use. This section lists procedures to use in case of accidental spills, as well as information about proper disposal.
Section 8: Control Measures. This section lists ways to avoid making contact with the human body such as respiratory protection, gloves, and ventilation.
the information above is quoted from the acs.org website.
5. Safety Equipment
Chemistry experiments are fun as long as everyone is safe. Make sure your experiment is safe by learning about recommended safety equipment.
a. Safety Goggles
When working with chemicals, wear splash-proof goggles to protect your eyes from spilled or splattered chemicals. Remember that goggles worn around your neck or forehead do not protect your eyes. Some state laws require every person in the laboratory to wear goggles.
b. Fire Blanket
Most clothing is flammable. If someone’s clothing catches on fire, wrap the person in a fire blanket to cut off the supply of oxygen to the flames, just like snuffing out a candle.
c. Safety Gloves
Disposable gloves like those used in the medical or dental profession are safety gloves. Some chemicals, like acids, are unsafe for skin contact. Although some substances can soak through gloves, this extra layer of protection can save hands from a chemical bum.
d. First-Aid Kit
For minor cuts, burns, and abrasions, have a first-aid kit handy. The supplies in a first-aid kit also can work for temporary assistance until proper medical attention is available.
e. Fire Extinguisher
If a flammable chemical is spilled near an open flame, a dry chemical fire extinguisher can be critical in putting out a fire.
For those of you who want to learn more about chemistry merit badge materials such as:
- Analytical Chemistry
- Biochemistry
- Inorganic Chemistry
- Separation
- Organic Chemistry
- Physical Chemistry
- Pollution
You can read the list of material in the pamphlet.
Careers in Chemistry
Did you enjoy the work you did to earn the Chemistry merit badge? If so, you might like to learn more about careers in chemistry and related fields.
To prepare for a career in any branch of chemistry, a high school student should take as many science and mathematics courses as possible.
1. Chemist
A chemist is a professional who normally has at least a Bachelor’s degree in chemistry, which prepares one to work in many different positions: industry, business, government, research institutions, and teaching,
Training Required
Chemists with a bachelor’s degree in chemistry attended a college or university and took about a quarter to a third of their courses in chemistry, with several supporting courses in physics, mathematics, and computer science.
Many chemists stay in school after earning a bachelor’s degree and earn advanced degrees. The master’s degree typically requires two years of study, and the doctorate requires at least three years beyond the master’s degree.
2. Industrial Chemist
Scarcely anything used by society is untouched by chemistry. Big chemical companies and petroleum companies, obviously, employ chemists, as do pharmaceutical companies, large manufacturers, utilities, and biotechnology companies, to name a few.
Most chemists work in the industry. A business using chemicals often has several choices for a chemist like technical sales and service, manufacturing, marketing, and research and development.
3. Chemical Engineer
A chemical engineer is a professional with a broad background in chemistry combined with training in manufacturing principles, physical design, and economics. Computers are a vital tool for chemical engineers. These professionals often command higher salaries than chemists and many other engineers.
They may work in all areas of manufacturing, government, and private consulting. A chemical engineer’s first position could be in a refinery, chemical plant, or engineering firm.
There are positions in which chemists and chemical engineers are interchangeable.
Chemical engineers can advance in company management or by private consultants. Chemical engineers have many doors open to them; they also can move on to careers in law or medicine.
Training Required
The student who enrolls in an engineering college takes basic engineering courses for the first two years and basic chemistry courses.
In the third or fourth year, in addition to some of the advanced courses that a chemistry major would take, there are specialized courses in chemical engineering.
The student would also have courses in physics, mathematics, and computer science
4. Chemical Technician
Chemical technicians are trained mainly in chemistry laboratory methods. They have knowledge of chemistry but not the extensive knowledge of theory that chemists and chemical engineers have.
Chemical technicians have many responsibilities in manufacturing plants, often as members of teams that include chemists, chemical engineers, craftspeople, production employees, and maintenance workers.
They may install or operate the machinery used to make chemicals. They may analyze products from a new process under testing, or they may be part of teams that run hundreds of analyses every day in a manufacturing plant.
Chemical technicians may join chemists in research and development or help chemical engineers run pilot plants.
Their training and skills fit them for many positions in the chemical industry. They have the flexibility to handle different responsibilities in a plant as needed.
Chemical technicians are not limited to the chemical industry, but could be useful anywhere there is a call for their skills in other industries that use chemicals.
In hospital laboratories testing medical samples or hospital materials, or in federal, state, and local government agency laboratories
Training Required
Two or three years of study beyond high school are needed to qualify for the associate’s degree given by many junior colleges and technical institutes.
Students training as chemical technicians takes courses in chemistry with an emphasis on laboratory procedures, test methods, and instruments used for analysis.
Besides chemistry, students usually take mathematics, English composition, technical report writing, and perhaps a few broadening courses-political science or sociology, for example.
5. Other Careers in Chemistry
Students who find that the laboratory is not for them but enjoy writing may find that technical writing or science reporting is a good career that combines their interests and talents.
A career as a science librarian also is a specialty that may be appropriate. A chemist or chemical engineer with a doctorate may specialize in research and development.
Chemists teach in high schools, technical institutes, colleges, and universities.
Chemists interested in law may become patent attorneys. This specialty is best served by an undergraduate degree in chemistry, followed by a law degree.
Another career that builds on an undergraduate degree in chemistry is high-level management in industrial companies. The aspiring manager would need a master’s degree in business administration.
Chemists finding their interests and talents pointing this way after they begin an industrial career can take night-school courses until they complete their degree requirements.
A bachelor’s degree in chemistry or chemical engineering can lead to interesting careers that overlap many other disciplines.
For example, a career in biochemistry, biotechnology, or medical research could begin with an undergraduate degree In chemistry.
There are many opportunities in environmental chemistry, clinical chemistry, geochemistry, and related areas in which chemistry is applied to other disciplines.
Chemistry students who think they may be interested in these careers dream about them by taking appropriate science electives as part of their undergraduate studies.
Also Read: Robotics Merit Badge
The Answer for Requirement Number 1a
Safety Equipment Used in a Chemistry Laboratory:
1. Safety Goggles: These are crucial to protect your eyes from chemical splashes, shards of broken glassware, and other hazards. The eyes are sensitive and vulnerable during experiments, making safety goggles a non-negotiable aspect of lab safety.
2. Lab Coat: A lab coat is a protective layer that prevents direct contact between your skin/clothing and harmful or corrosive chemicals. It also protects you from fire hazards as most lab coats are made of flame-resistant material.
3. Gloves: Specialized lab gloves guard your hands against chemical burns, harmful biological substances, or extreme temperatures. Depending on the type of work, different materials like latex, nitrile, or neoprene might be used.
| Safety Equipment | Purpose |
|---|---|
| Safety Goggles | Protect eyes from chemical splashes and broken glassware. |
| Lab Coat | Prevent direct contact between skin/clothing and harmful substances, provide fire resistance. |
| Gloves | Protect hands against chemical burns, harmful biological substances, and extreme temperatures. |
The Answer for Requirement Number 1b
A Safety Data Sheet (SDS), previously known as a Material Safety Data Sheet (MSDS), is a detailed informational document prepared by the manufacturer or importer of a hazardous chemical. It describes the physical and chemical properties of the product.
The information included in this document is the melting point, boiling point, flash point, toxicity, health effects, first aid, reactivity, storage, disposal, protective equipment, and spill-handling procedures.
An SDS is essential for various reasons:
- It provides critical information about hazardous chemicals.
- It describes safe handling, use, storage, and emergency procedures.
- It assists in the creation of active workplace safety and training measures.
| Safety Data Sheet (SDS) | Purpose |
|---|---|
| Provides critical information | Details about hazardous chemicals are included. |
| Safe handling procedures | Guidelines for handling, use, storage, and emergencies. |
| Supports safety measures | Assists in creating workplace safety and training programs. |
The Answer for Requirement Number 1c
Obtaining a Safety Data Sheet (SDS) for paint and an insecticide allows for a comparative analysis of their toxicity, disposal, and safe handling. Remember, SDS are unique to each product, so specifics will differ. Here’s a generalized comparison:
Toxicity: Paint often has low acute toxicity unless ingested or inhaled, but long-term exposure can cause respiratory issues. Insecticides are generally more toxic, especially to children and pets. Prolonged exposure can lead to serious health problems.
Disposal: Both products must be disposed of properly to prevent environmental harm. Unused paint can often be recycled at specific facilities, while empty cans can go to a landfill. Insecticides require special disposal procedures – they should never be poured down the drain or placed in the regular trash.
Safe handling: Both should be used in well-ventilated areas and kept out of reach of children and pets. While using insecticides, it’s advisable to wear protective clothing.
| Product | Toxicity | Disposal | Safe Handling |
|---|---|---|---|
| Paint | Low acute toxicity but can cause issues over time. | Can often be recycled or go to a landfill. | Use in a well-ventilated area, store safely. |
| Insecticide | Generally more toxic, especially to kids and pets. | Requires special disposal procedures. | Use protective clothing, avoid skin contact, store safely. |
The Answer for Requirement Number 1d
Safe storage of chemicals involves keeping them in an appropriate place where they are not likely to cause harm. This applies to homes, schools, communities, and the environment in the following ways:
Home: Chemicals should be stored in a locked cabinet or out of reach of children and pets. Store them in a cool, dry place away from food and drink.
School: In labs, chemicals should be organized according to compatibility, not alphabetically. Flammable substances should be stored in a fireproof cabinet.
Community: Businesses should store chemicals per local regulations, usually in a designated storage area with proper ventilation, temperature control, and spill cleanup supplies.
Environment: Safe storage can prevent chemicals from leaking into the environment, contaminating water sources or harming wildlife. It is important to follow local regulations on chemical storage to protect the ecosystem.
| Place | Safe Storage Guidelines |
|---|---|
| Home | Keep chemicals locked away or out of reach, in a cool, dry place away from food. |
| School | Store chemicals according to compatibility, use fireproof cabinets for flammable substances. |
| Community | Prevent leakage to protect water sources and wildlife, and follow local regulations. |
| Environment | Store chemicals according to compatibility, and use fireproof cabinets for flammable substances. |
The Answer for Requirement Number 2a
Before conducting the experiment, one would predict that when an iron nail is placed in a copper sulfate solution, a chemical reaction would take place. The iron (Fe) would displace the copper (Cu) in the copper sulfate (CuSO4) solution because iron is more reactive than copper.
After conducting the experiment, one would observe that the iron nail starts to develop a reddish-brown coating. This is because the iron displaces the copper from the copper sulfate solution, producing iron sulfate and copper. The copper deposits on the iron nail, giving it a reddish-brown color.
The conclusion is that the chemical reaction took place as predicted. The iron did displace the copper from the copper sulfate solution, which is why the nail developed a coppery coating.
Comparing the prediction with the conclusion, we find that they align well with each other.
The formula for the reaction is as follows:
Fe (s) + CuSO4 (aq) -> FeSO4 (aq) + Cu (s)
This represents the iron (Fe) reacting with the copper sulfate (CuSO4) to produce iron sulfate (FeSO4) and copper (Cu).
| Prediction | Observation | Conclusion | Chemical Reaction |
|---|---|---|---|
| Iron nails developed a reddish-brown coating. | Iron nail developed a reddish-brown coating. | Iron displaced copper from the solution, as predicted. | Fe + CuSO4 -> FeSO4 + Cu |
The Answer for Requirement Number 2b
To separate sand (or gravel) from water, you can use a simple filtration method. Pour the mixture through a fine mesh or filter paper. The water will pass through, leaving the sand or gravel behind.
To separate table salt from water, you can use the evaporation method. By heating the salt-water mixture, the water will evaporate, leaving the salt behind.
To separate oil from water, you can utilize the process of decantation. Due to differences in density, oil floats on water. By slowly pouring out the water, you can separate it from the oil.
Separating gasoline from motor oil requires a process called distillation. This process takes advantage of the different boiling points of the two substances. By heating the mixture, the gasoline will evaporate first due to its lower boiling point, and can then be collected separately.
These methods are commonly used in many practical processes. For example, filtration is often used in water treatment plants to remove solid impurities. Evaporation is used in salt production. Decantation is used in oil spill cleanup.
Distillation is extensively used in oil refineries to separate different components of crude oil. The methods might differ depending on the properties of the substances involved such as their boiling points or densities.
| Separation Process | Method Used | Practical Processes |
|---|---|---|
| Sand from Water | Filtration | Water treatment |
| Table Salt from Water | Evaporation | Salt production |
| Oil from Water | Decantation | Oil spill cleanup |
| Gasoline from Motor Oil | Distillation | Oil refining |
The Answer for Requirement Number 2c
A chemical reaction and a physical change are two different ways that substances can undergo a transformation, but each one has distinct characteristics.
A chemical reaction involves a process that changes one set of chemical substances to another. During a chemical reaction, the molecular or ionic structure of substances is altered, leading to the formation of new substances with different properties.
Examples include the rusting of iron or the baking of a cake. Indicators of a chemical reaction might include color change, gas production, heat or light production, or the formation of a precipitate.
On the other hand, a physical change does not alter the composition of a substance. Instead, it changes the physical properties of the substance like shape, size, or state of matter. An example of a physical change is water boiling into steam or a paper being cut into pieces. A physical change is usually reversible.
| Type of Change | Definition | Examples |
|---|---|---|
| Chemical Reaction | A process that alters the molecular or ionic structure of a substance. | Rusting of iron, baking a cake |
| Physical Change | A process that alters the physical properties of a substance without changing its composition. | Water boiling into steam, cutting a paper |
The Answer for Requirement Number 3
A Cartesian diver is a simple device that demonstrates the principles of buoyancy and gas behavior under different pressures and temperatures.
To construct a Cartesian diver, you typically use a small, tightly sealed container (like a plastic pipette or small tube) partially filled with air and placed in a larger container full of water. When you press down on the larger container, the pressure increases, compressing the air in the small container and allowing more water to enter.
This increases the density of the small container (the diver), causing it to sink. Release the pressure, and the process reverses: the air in the diver expands, forcing the water out, decreasing the diver’s density and causing it to float.
This principle reflects how gases behave under different pressures and temperatures – a concept described by the ideal gas law, which states that the pressure and volume of a gas are inversely proportional at a constant temperature.
The behavior of gases under varying pressure and temperature also affects activities like backpacking at high altitudes and scuba diving. For a backpacker at high altitudes, the air pressure decreases, making the air less dense and leading to less oxygen availability.
This can cause altitude sickness. For a scuba diver, the pressure increases with depth, affecting how gases like nitrogen are absorbed into the body, which can lead to conditions like decompression sickness if the diver ascends too rapidly.
| Activity | Gas Behavior | Effect |
|---|---|---|
| Backpacking at high altitudes | Air pressure decreases, making air less dense. | Less oxygen availability can cause altitude sickness. |
| Scuba diving | Air pressure increases with depth. | Increased absorption of gases like nitrogen can cause decompression sickness if ascending too rapidly. |
The Answer for Requirement Number 4a
When you cut a round onion into small chunks and separate them into three portions, each one undergoes a different transformation when cooked to different extents, affecting its taste.
- Raw Onion: The taste is strong, sharp, and somewhat spicy. The sulfur compounds are intact, giving the raw onion its pungent smell and eye-watering effect.
- Partially Cooked Onion (Translucent): The taste becomes softer, less pungent, and slightly sweet. Heat breaks down the harsh sulfur compounds into milder substances. The onion becomes translucent as the heat breaks down its cell structure, releasing water.
- Caramelized Onion: The taste is sweet, with a deep flavor profile. As the onion cooks further, the natural sugars break down and caramelize, creating complex flavors. The onion turns brown due to the Maillard reaction, a chemical reaction between amino acids and sugars that gives browned food its distinctive flavor.
The changes in the taste of the onion reflect changes at the molecular level. Heat triggers chemical reactions that break down the sulfur compounds and natural sugars in the onion, transforming its flavor and color.
| Stage | Taste | Molecular Changes |
|---|---|---|
| Raw Onion | Strong, sharp, spicy | Sulfur compounds are intact |
| Partially Cooked Onion | Softer, less pungent, slightly sweet | Sulfur compounds are broken down into milder substances |
| Caramelized Onion | Sweet, deep flavor | Sugars break down and caramelize due to Maillard reaction |
The Answer for Requirement Number 4b
Toothpaste and an abrasive household cleanser share some chemical similarities and differences. Both products contain abrasive elements to aid in the removal of unwanted materials. However, the specific chemicals used, their concentration, and their coarseness significantly differ to suit their respective purposes.
- Toothpaste: Its abrasive elements, such as hydrated silica or calcium carbonate, are gentle enough not to damage the tooth enamel. Fluoride, a common component, helps to protect teeth by strengthening enamel and preventing cavities. Flavorings and sweeteners are also added for a pleasant taste.
- Abrasive Household Cleanser: This product contains harsher abrasives, such as silica, and chemicals like bleach for more robust cleaning tasks. These ingredients can remove stubborn dirt and grime but would be far too aggressive for use in the mouth.
The end use of a product greatly influences its chemical formulation. For instance, toothpaste is designed for oral use and therefore needs to be safe to ingest, pleasant tasting, and gentle on teeth and gums.
Conversely, a household cleanser is created to effectively clean hard surfaces, thus requiring a more potent and abrasive chemical formulation.
| Product | Purpose | Key Chemical Components | Abrasiveness |
|---|---|---|---|
| Toothpaste | Clean teeth and protect enamel | Hydrated silica, calcium carbonate, fluoride | Low |
| Abrasive Household Cleanser | Clean hard surfaces and remove grime | Silica, bleach | High |
The Answer for Requirement Number 4c
Oil and water do not mix due to their distinct molecular structures. Water is a polar molecule, which means it has a positive charge on one side and a negative charge on the other. Oil, on the other hand, is a non-polar molecule, which means it doesn’t have these charges.
The principle “like dissolves like” applies here, meaning that polar substances dissolve other polar substances, and non-polar substances dissolve other non-polar substances. Therefore, water and oil do not mix.
However, you can facilitate the mixing of these two substances by introducing an emulsifier. Emulsifiers are molecules with a polar (water-loving) end and a non-polar (oil-loving) end. A common household example of an emulsifier is dish soap.
| Step | Process | Observation |
|---|---|---|
| 1 | Mix oil and water | Oil and water separate, with oil floating on top because it’s less dense |
| 2 | Add dish soap and mix again | The water, oil, and dish soap combine into a milky emulsion |
After adding the dish soap and stirring, you’ll notice that the oil droplets are suspended in the water. This happens because the dish soap molecules surround the oil droplets, with their polar ends facing the water and their non-polar ends facing the oil. This allows the oil and water to mix, forming an emulsion.
The Answer for Requirement Number 5
The five classical divisions of chemistry are organic chemistry, inorganic chemistry, analytical chemistry, physical chemistry, and biochemistry.
| Division | Description | Everyday Application |
|---|---|---|
| Organic Chemistry | This branch focuses on compounds that contain carbon, including hydrocarbons and their derivatives. Organic chemistry is primarily associated with life and substances derived from life. | Organic chemistry is essential in developing pharmaceuticals, dyes, detergents, and polymers, including plastics. If you take medicine or use plastic products, you are experiencing the results of organic chemistry. |
| Inorganic Chemistry | Inorganic chemistry studies materials such as metals and gases that do not have carbon as part of their makeup. It’s involved in the study of minerals found in the Earth’s crust. | Inorganic chemistry impacts everyday life in various ways, such as the minerals in our food, the oxygen we breathe, and the water we drink. |
| Analytical Chemistry | Analytical chemistry involves the analysis of materials to determine what substances are present, and in what quantities. | This is used in food testing to determine nutritional content or detect contaminants. It’s also applied in environmental testing to measure pollutant levels. |
| Physical Chemistry | This is a combination of physics and chemistry. It seeks to measure, explain, and correlate the physical properties of substances. | Physical chemistry helps in understanding phenomena like boiling or freezing points, which we encounter in everyday cooking or weather changes. |
| Biochemistry | Biochemistry is the study of chemical reactions that occur in living organisms. | Biochemistry influences our understanding of biological processes, such as digestion, DNA replication, protein synthesis, etc. It is foundational in the field of medicine and nutrition. |
These divisions, although distinct, often overlap in practical applications, leading to advancements in various fields that directly affect our everyday lives.
The Answer for Requirement Number 6a
Two government agencies responsible for tracking the use of chemicals for commercial or industrial use are the Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA).
| Agency | Responsibilities |
|---|---|
| Environmental Protection Agency (EPA) | The EPA has the crucial role of protecting human health and the environment. It establishes and enforces regulations concerning environmental protection based on laws passed by Congress. The EPA’s responsibilities include monitoring industrial processes that involve chemicals, regulating the disposal of hazardous waste, and establishing air and water quality standards. The EPA also provides information about industrial emissions and waste disposal to the public to increase transparency and ensure public safety. |
| Occupational Safety and Health Administration (OSHA) | OSHA, on the other hand, is responsible for ensuring safe and healthy working conditions for workers by setting and enforcing standards and by providing training, outreach, education, and assistance. This includes tracking and regulating the use of chemicals in the workplace to protect employees from potential health hazards. |
To further delve into the role of the EPA: This agency regulates the use, manufacture, and disposal of chemical substances—like pesticides, toxic substances, and chemicals that deplete the ozone layer—to prevent adverse effects on the environment.
Their key responsibilities also include assessing environmental conditions and conducting research on the adverse effects of contaminants and pollutants. The EPA actively collaborates with industries, national, state, local, and tribal governments, non-profit organizations, and educational institutions to address environmental issues.
The Answer for Requirement Number 6b
Pollution is the introduction of harmful materials, known as pollutants, into the environment. These pollutants can take the form of chemical substances or energy, such as noise, heat, or light.
Pollution is often the byproduct of human activities and can have severe effects on the natural world and the living organisms that inhabit it.
Chemical impacts on the ozone layer and global climate change are two significant environmental issues.
Ozone Layer Depletion
The ozone layer is a region of the Earth’s stratosphere that contains a high concentration of ozone (O3) molecules. It plays a vital role in protecting life on Earth by absorbing the majority of the sun’s harmful ultraviolet radiation.
However, certain chemicals, especially chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and other halogenated ozone-depleting substances, have been found to deplete the ozone layer.
When these chemicals are released into the atmosphere, they can take years to ascend to the stratosphere, where they are broken apart by solar radiation, releasing chlorine atoms that catalyze the destruction of ozone. This process has led to the creation of the so-called “ozone holes.”
| Ozone Depleting Chemical | Impact |
|---|---|
| Chlorofluorocarbons (CFCs) | When broken down by solar radiation, they release chlorine atoms, which catalyze the destruction of ozone molecules. |
| Hydrochlorofluorocarbons (HCFCs) | Similar to CFCs, but they contain hydrogen atoms, which makes them less stable and therefore less damaging to the ozone layer as they break down more quickly. |
Global Climate Change
Global climate change, often referred to as global warming, is the long-term alteration in Earth’s climate and weather patterns. It’s primarily a result of human activities, notably the burning of fossil fuels like coal, oil, and gas, which increase the concentration of greenhouse gases in the Earth’s atmosphere.
| Greenhouse Gas | Impact |
|---|---|
| Carbon Dioxide (CO2) | Burning fossil fuels for electricity, heat, and transportation is the largest single source of global greenhouse gas emissions, which leads to an increased concentration of CO2 in the atmosphere, trapping heat and contributing to global warming. |
| Methane (CH4) | This is emitted during the production and transport of coal, oil, and natural gas. Methane is also emitted by livestock and other agricultural practices, as well as by the decay of organic waste in municipal solid waste landfills. It’s a more potent greenhouse gas than CO2. |
Both these issues illustrate the profound impact of human activities on the planet’s natural systems and underscore the need for sustainable practices to mitigate environmental damage.
The Answer for Requirement Number 6c
Let’s delve into the impact of the production of aluminum cans on the environment from a chemistry perspective.
Aluminum cans are commonplace in our daily lives, primarily used for packaging drinks. The process of producing these cans, however, has notable environmental implications.
Bauxite Mining
The production of aluminum cans starts with the mining of bauxite, an ore that contains a high percentage of aluminum oxide. The extraction process is destructive to local ecosystems, as it involves clearing vegetation, stripping the topsoil, and ultimately reshaping the landscape.
Bayer Process
After mining, the bauxite is refined into alumina (aluminum oxide) through the Bayer process. This involves crushing the ore and mixing it with a caustic soda solution to separate alumina from the rest of the ore.
This process requires significant energy and creates a byproduct known as “red mud” or bauxite residue, which is highly alkaline and can pollute waterways if not properly managed.
Hall-Héroult Process
The alumina is then transformed into aluminum through the Hall-Héroult process, which involves electrolysis – a process that uses a significant amount of electricity. Carbon electrodes used in the process are consumed, producing carbon dioxide, a greenhouse gas contributing to global warming.
| Production Step | Environmental Impact |
|---|---|
| Bauxite Mining | Leads to deforestation and habitat destruction |
| Bayer Process | Creates ‘red mud’ waste, potential for water pollution, high energy demand |
| Hall-Héroult Process | High electricity usage, carbon dioxide emissions |
Recycling aluminum cans significantly reduces these impacts. It saves about 95% of the energy required to produce new cans from bauxite, reduces mining waste, and decreases greenhouse gas emissions.
Unfortunately, not all cans are recycled, leading to landfill waste, as aluminum takes about 200-500 years to fully degrade in a landfill.
In summary, while aluminum cans are convenient for consumers, their production and disposal have a significant impact on the environment, highlighting the importance of recycling and sustainable practices.
The Answer for Requirement Number 6d
Phosphates are integral components in both fertilizers and laundry detergents, serving unique and vital purposes in each.
Fertilizers: Phosphates, as phosphorus compounds, are one of the three primary nutrients needed for plant growth, alongside nitrogen and potassium. They are critical for energy transfer and storage in plants, aiding in photosynthesis, nutrient transportation, and the formation of DNA.
Laundry Detergents: In laundry detergents, phosphates act as water softeners and improve the cleaning power. They help to break down grease and remove stains by separating dirt from the fabric and preventing it from re-depositing on the clothes.
| Use of Phosphates | Purpose |
|---|---|
| Fertilizers | Boosts plant growth by aiding in energy transfer, nutrient transportation, and DNA formation |
| Laundry Detergents | Acts as water softeners, enhancing cleaning efficiency by separating dirt from fabric |
However, phosphates have a significant environmental impact, particularly when used in fertilizers. Excess phosphates from agricultural runoff can seep into rivers, lakes, and oceans, leading to a phenomenon called “eutrophication.” Eutrophication stimulates excessive growth of algae (algal blooms), which deplete the water’s oxygen levels when they decay, causing the death of other marine life, a situation known as a “dead zone.”
Moreover, the extraction of phosphate rocks for fertilizer production has environmental implications, including landscape alteration, habitat destruction, and water contamination.
Due to these detrimental environmental effects, and the fact that natural water-softening alternatives exist, phosphates have been phased out from laundry detergents in many countries. This shift helps reduce the phosphate levels in wastewater and subsequently lessen the occurrence of harmful algal blooms.
In summary, while phosphates are beneficial to both plant growth and laundry cleaning, their environmental implications, particularly eutrophication, have led to regulatory action limiting their use in detergents.
The Answer for Requirement Number 7b
Chemistry is a diverse field, offering various roles, including chemists, chemical engineers, chemical technicians, and industrial chemists. Each of these positions differs significantly in their tasks, and hence, they each require a unique set of educational qualifications and training.
- Chemists: Chemists study substances at the atomic and molecular levels and the ways in which substances react with others. They use their knowledge to develop new and improved products and to test the quality of manufactured goods.Education and Training: A minimum of a bachelor’s degree in chemistry or a related field is required. However, a master’s degree or Ph.D. is often needed for research positions.
- Chemical Engineers: Chemical engineers apply the principles of chemistry, biology, physics, and math to solve problems that involve the use of fuel, drugs, food, and many other products. They design processes and equipment for large-scale manufacturing.Education and Training: A bachelor’s degree in chemical engineering is required. Some positions may require a graduate degree.
- Chemical Technicians: Chemical technicians use special instruments and techniques to assist chemists and chemical engineers in researching, producing, and testing chemical products.Education and Training: Generally, an associate’s degree in chemistry or a related field is required. Many also have a bachelor’s degree.
- Industrial Chemists: Industrial chemists work with chemical manufacturing processes in industries. They contribute to the development, optimization, and monitoring of industrial operations.Education and Training: Typically, a bachelor’s degree in chemistry or chemical engineering is required. Some positions may demand a master’s degree or Ph.D., particularly for research-oriented roles.
| Role | Education and Training |
|---|---|
| Chemists | Bachelor’s degree in chemistry or related field; Master’s degree or Ph.D. for research positions |
| Chemical Engineers | Bachelor’s degree in chemical engineering; Graduate degree for some positions |
| Chemical Technicians | Associate’s degree in chemistry or related field; Bachelor’s degree for some positions |
| Industrial Chemists | Bachelor’s degree in chemistry or chemical engineering; Master’s degree or Ph.D. for research-oriented roles |
Remember, this is a general overview, and the specific requirements may vary based on the role’s complexity, the industry, and the hiring organization’s preferences.
