Chemistry: Top 10 Questions

March 2017

Thanks to Dr. Kathryn Devine, associate professor of physics at the College of Idaho and Dr. Christopher Saunders, chemistry lecturer at Boise State University, for the answers.

1: What exactly is chemistry?

The simple answer is that chemistry is the study of matter, and matter is the stuff that makes up everything that you see and feel around you. You could say that chemistry is the study of everything and how everything in the universe interacts with each other. (From Tyler at McDonald Elementary School in Moscow)

2: What are atoms?

Atoms are the fundamental building blocks of matter. If you take matter and look at the tiniest things that it is made of, you will find atoms. For example, hydrogen is an atom. Oxygen is an atom. If you take two hydrogen atoms and an oxygen atom and put them together, you will have a molecule of water. Everything around us is made from molecules and atoms. When put together, these tiny particles build our world. (From Halie at Mountain View Elementary School in Boise)

3: Why are some chemicals poisonous to people and others are not poisonous?

That is a complicated question. Even things that you may not think of as being poisonous or toxic to people, can be toxic in the right dosages. In determining if something is harmful to someone, it is important to know how much of the substance that person has had exposure to. (From Ashley at Russell Elementary School in Moscow)

4: How did scientists decide which elements are on the periodic table, and in what order they are?

The person who is credited with the construction of the periodic table is Dmitri Mendeleev. He organized the elements based on the number of protons that you find in the nucleus. All of the elements that we know are on the periodic table and, we continue to add new elements. The order and the way that the periodic table is organized tells us something about the chemical properties of those elements. (From Amelia at McDonald Elementary School in Moscow)

5: How is baking chemistry?

When you bake, you rely on chemical reactions to get certain results, just like you do with chemistry. One of the most common examples is the use of baking soda or baking powder. Although there are differences between the two, both of them rely on acid-based chemistry. For example, when you use baking soda in a cake mix, the baking soda will dissolve with moisture as it heats. It will then interact with an acid, and that reaction produces carbon dioxide, causing the mixture to rise, becoming what we know of as cake. (From Emerson at McDonald Elementary School in Moscow)

6: How does liquid nitrogen and dry ice stay so cold?

Anything that is at an extreme temperature or a different temperature from the area around it, when left out in the open, it will reach thermodynamic equilibrium. This means that it will eventually become the same temperature as the room around it. For dry ice and liquid nitrogen to stay cold, you have to prevent that from happening. To do this, you need to put them in something insulated. (From Cora at Russell Elementary School in Moscow)

7: Why are Newton's three laws so important?

Newton's three laws describe forces in motion. These laws allow physics to be described in terms of rules and lay the groundwork for how we teach modern physics. (From Scott at Dalton Elementary School in Dalton Gardens)

8: What does H2O stand for?

H2O is an example of a chemical formula. The way that scientists write chemical formulas tells you what the composition of the molecule is. With H2O, the "H" stands for Hydrogen, the "O" stands for Oxygen, and the "2" is referencing how many atoms of hydrogen there are per oxygen. We call H2O, water. Water has two atoms of hydrogen and one atom of oxygen. (From Louie at Riverside Elementary School in Boise)

9: How did people discover electrons and neutrons?

The person who is credited with the discovery of electrons is J. J. Thompson. In his experiments, he discovered that if you looked at different materials and exposed them to electricity (you put a lot of energy into them), they would produce a beam of rays. We call them cathode rays. All of these rays are negatively charged. If you exposed them to something that is positively charged, the beam of particles would be attracted. Later on, the term electron started being used for those particles. Thompson won the Nobel Prize in 1906 for this discovery. (From Ella at Christine Donnell School in Boise)

10: How do light bulbs work, and how are light bulbs now more efficient?

There are the "old fashioned" light bulbs that have the filament inside. A filament is a wire. When you put it into a light bulb and screw that into a socket, a current runs through it. This heats the filament up and it starts to emit light. The light is in the form of visible light that we can see, and in the form of infrared light that we can feel as heat. If you were to put your hand near one of the older bulbs, you would feel the heat that it emits. Newer light bulbs have a CFL, or compact fluorescent light bulb. These light bulbs have a gas inside of them. When you screw one of these bulbs into a socket, the current actually excites the electrons, creating a higher energy level in the gas inside the light bulb. Then, as those electrons cascade back down, they give off photons. The photons hit the coating on the inside of the light bulb, which causes a phosphorescence of fluorescent reaction. That gives off the light we can see with our eyes. The reason these bulbs are more efficient is that they do not emit as much heat. In other words, they give off energy but more in the form of light than heat. (From Caleb at Riverside Elementary School in Boise)

November 2009

Thanks to Henry Charlier, Associate Director of Chemistry, Boise State University; and Daniel Stelck, University of Idaho for the answers.

1: How many different kinds of chemicals are there?

There are 20 million chemicals known to mankind and that number increases substantially every year. Everything that you see is a chemical. (From Kaylee in Mrs. Little's class at Ross Elementary School in Kuna)

2: Do atoms change when matter changes?

Atoms can combine differently with other chemicals to make compounds, but for the most part, an atom is not going to change and is always an atom. Only if you split it apart with nuclear fission will you create new atoms. (From Kristopher in Mrs. Chaffee's class at Valley View Elementary School in Boise)

3: What is the Periodic Table of Elements?

The Periodic Table is a way to organize and list the different elements. All elements have atomic structures - the number of electrons and protons. The table lets us see how many electrons are in a certain atomic orbital. By looking at it, we can understand trends and predict the behaviors of several of the elements. (From Marie in Mrs. Childer's class at Hayden Meadows Elementary School in Hayden)

4: Why is chemistry important for everyday life?

Everything we do in life is chemistry. When we breathe, we change oxygen to carbon dioxide and give ourselves energy. When we eat, we digest food. This also gives us energy. Biochemists try to make drugs work better to treat illnesses and cancers. All of these things involve chemistry. It's important in everything we do. (From Allyssa in Miss Miller's class at Caldwell Adventist Elementary School in Caldwell)

5: How many chemicals are in the human body?

There are many types of chemicals in your body. There are proteins, fats, sugars, and DNA. All of these are chemicals and there are thousands and thousands of them. (From Molly in the Idaho Virtual Academy from Emmett)

6: Why does baking soda sizzle when it hits vinegar?

When baking soda and vinegar are combined, carbon dioxide, a gas, is created. The gas is trapped in the liquid and when it fizzles out, it creates a fizzling (sizzling) sound. (From Miles in Mrs. McCoy's third grade class at Donnelly Elementary School in Donnelly)

7: What is the most dangerous chemical?

There are all sorts of dangerous, or toxic, chemicals. Some examples are cyanide and radioactive chemicals, like uranium. Even water can be as dangerous as any toxic chemical because people drown in water. Depending on the concentration of the chemical, all of them could be dangerous. (From Megan in Mrs. Hunt's class at Cynthia Mann Elementary School in Boise)

8: If everything is made from atoms, are atoms different?

Atoms are different because they have a different number of protons or neutrons (different combinations). Most living things are made up of the same types of atoms. It's how they are combined that makes them different. (From Caleb in Ms. Miller's class at Caldwell Adventist Elementary School in Caldwell)

9: How do you find new chemicals?

To find new chemicals, scientists and chemists combine different numbers of atoms and/or different types of atoms and see if they connect correctly. If they connect together correctly, they try to determine if this is a new structure. It's like putting tinker toys together. We combine atoms in different ways to see if they have different physical and chemical properties. When they do, we have a new chemical. (From Karie in Mrs. Rice's class at Purple Sage Elementary School in Caldwell)

10: Are there different kinds of chemistry or only one kind?

There are several different types of chemistry. Some examples are biochemistry, organic chemistry, forensic chemistry, physical chemistry, medicinal chemistry and many more. (From Stuart in Mrs. Amber's class at Cynthia Mann Elementary School in Boise)

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