Chemical Reactions

Which of these is an example of a chemical reaction?

• Burning Wood

• Substance producing a smell

• Water changing color because of adding Kool-Aid

• All of the above

What is the substance produced by a chemical reaction called?

• Product

• Reactant

• Resultant

• None of the above

What does a catalyst do to a chemical reaction?

• Slows down the rate of a chemical reaction

• Starts the reaction

• Speeds up the raction

• Stops the reaction

One example of a chemical reaction is when H20 (water) melts and changes state from ice to liquid

• True

• False

Which of the following models best demonstrates a balanced chemical equation?

• F
• G
• H
• J

The formula below represents the most common carbohydrate known as glucose. Which information can be determined from the chemical formula?
C₆H₁₂O₆

• The structural arrangement of the atoms in a glucose molecule
• The color of a glucose molecule
• The size of a glucose molecule
• The number of atoms of each element in a glucose molecule

In a chemical equation, is it true that -

• the reactant side and product side can have different numbers of atoms for each element
• there can be different elements on the reactant side and the product side
• an element or compound must be accompanied by a phase change
• the coefficients indicate the number of molecules of each reactant used and the number of molecules of each product made

The chemical formula for glucose, a simple sugar, is C₆H₁₂O₆. The formula for ethanol is C₂H₆O. What accounts for the differences in these compounds?

• The elements that make up glucose are different than the elements that make up ethanol
• The ratio of the elements is different in ethanol than in glucose
• The chemical properties of the elements are different in glucose and ethanol
• Glucose has more elements than the ethanol

Two clear colorless solutions were combined.
The student observed that the temperature changed from 25 •C to 23 •C when the solutions were combined and that a white substance rapidly formed and settled to the bottom of the container. What most likely happened to produce these results?

• One of the original compounds came out of solution
• The solutions reacted chemically
• Some of the water froze into ice crystals
• Rapid evaporation of water occurred, leaving a solid

The equation below represents a chemical reaction that occurs in living cells. How many atoms are represented in the reactants of this equation?

• 6
  6
• 12
  12
• 24
  24
• 36
  36