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Top Questions About Chemistry

Q: Why does putting bleach in food coloring make the color go white??

From Gabby in Des Moines, IA - 6th grade

A: Bleach works by breaking chemical bonds of chromophores. Chromophores are parts of a molecule that has color. This changes the molecule so that it either has no color or else reflects color outside the visible spectrum. This is why you often see a white color when bleach is applied to certain items.
Question answered by: Symbi Scientist, Joy Jackson


Q: Why are bacteria single cells?

From Sahal in Des Moines, IA - 6th grade

A: Bacteria have one cell because they are unicellular creatures. They lack a nucleus and do not have distinct organelles. Bacteria are quite simple organisms and are not nearly as complex as humans.
Question answered by: Symbi Scientist, Heather Edwards


Q: Why does baking soda and vinegar bubble when mixed together?

From Kourtney in Des Moines, IA - 6th grade

A: Vinegar is an acid and baking soda is a base. When a base and an acid are mixed together they will start to react with one another. This reaction occurs in the form of bubbles that we can see.
Question answered by: Symbi Scientist, Heather Edwards


Q: From class, why did the piece of glass appear to be clear, but when it shattered into small pieces, the color changed to a blue/green color?

From Mrs. Greeno's Block-1 Science Class in Des Moines, IA - 7th grade, Harding Middle School

A: This is a great observation! The sand that is used to make window glass contains FeO (iron oxide) impurities. These impurities only allow green light to pass through them. The resaon we see the color in the edges of the glass and not through the front side of the glass is that the amount of FeO (iron oxide) is rather small. This means that we can see the color more easily through thick sections of the glass, like the edge.
Question answered by: Symbi Engineer, Christian Bischoff


Q: What chemicals go together?

From Linda in Des Moines, IA - 8th grade

A: There are many different chemicals. The reaction of different chemicals combined have different outcomes. One has to be careful and study the chemicals that they are going to use to do certain reactions. There are many outcomes from mixing chemicals together for example, no reaction, an explosion, a new compound, or even decomposition of the chemicals that were used. A good example would be baking a cake. When mixing the ingredients together, one might accidently add the wrong ingredient, such as vinegar to a cake batter that has baking soda and that could create bubbling. If the person forgot to add just one ingredient, than the cake batter might not bake the way they wanted it to or taste right. Always remember that mixing chemicals together can be dangerous so it is very important to always look up safety hazards and follow safety procedures.
Question answered by: Symbi Scientist, Heather Edwards


Q: What are chemicals?

From Ruth in Des Moines, IA - 6th grade

A: The term chemical is very broad. We could have chemical elements, chemical compounds, or chemical mixtures. Chemical elements are a chemical substance that is made up of a particular kind of atoms and hence cannot be broken down or transformed by a chemical reaction into a different element. A chemical compound is a chemical substance that is composed of a particular set of molecules or ions. Two or more elements combined into one substance through a chemical reaction form a chemical compound. Chemical mixtures are a collection of chemical elements or compounds that do not react with each other and they can be separated into the component substances by purely mechanical processes. Chemical elements, compounds and mixtures can be solids, liquids, or gases.

When discussing what chemicals go together, we need to decide what we want the chemicals to do. With these chemicals, there are three general things that can happen. 1. No reaction. 2. Controllable reaction. 3. Run Away reaction. This is where putting chemicals together gets tricky. For instance, you can put small pieces of iron and sulfur together and at room temperature, there is no reaction (you have a mixture then.). However, if you heat them up, then they chemically bond to form iron(II) sulfide (chemical compound). So things like temperature effect how different chemicals react with each other.

If we were looking to store the chemicals, there are several ways to classify chemicals. One way is acids (low pH) and bases (high Ph). Another is by organics (contains carbon) and inorganics (no carbon). Often, chemicals stored in a lab are separated by these definitions. This is because when acids and bases react with each other, they can form explosions or fires if not controlled properly. Likewise, some inorganics such as sodium, is to be kept separate from organics that might have water because sodium and water do not mix well. The bigger the lab, the more variations there can be.

There are millions and millions of chemicals, many of which are made by other chemicals, and thousands of ways to make them. Most of these chemicals have been made in a lab and so knowing how to store them so they don’t react is important, but also knowing how to organize them will help you to control the reactions.
Question answered by: Symbi Engineer, Peter Hondred