Chemical Equations (previous version)

What is a chemical reaction?

• a.a process of bonding substances together
• b.a process that leads to filled valence shells
• c.a process that releases or consumes energy
• d.all of the choices

What is a chemical equation?

• a.a diatomic molecule
• b.a shorthand representation of a chemical bond
• c.a shorthand representation of a chemical reaction
• d.a substance

What are substances on the left side of a chemical equation called?

• a.electrons
• b.groups
• c.products
• d.reactants

What are substances on the right side of a chemical equation called?

• a.electrons
• b.groups
• c.products
• d.reactants

What does the number in front of the molecular symbol mean?

• a.It shows that there is only one molecule present in a reaction
• b.It shows the number of reactions that took place
• c.It shows the number of molecules in the reaction
• d.All of the choices

Can the subscripts in a chemical reaction be changed?

• a.Cannot be determined
• b.Maybe, depending on the energy released
• c.No, they define the molecules in the reaction
• d.Yes, to balance the equation

Chemical reactions proceed under the law of definite proportions:

• a.always
• b.cannot be determined
• c.never
• d.sometimes

16.05 g of methane reacts completely with 64.00 g of oxygen to form carbon dioxide and water. What will be the total weight of the CO₂ and H₂O?

• a.16.05
• b.64
• c.80.05
• d.the weight cannot be determined

What is a limiting reactant?

• a.a reactant that is found in excess in a chemical reaction
• b.a reactant that is not present
• c.a reactant that will be consumed completely during a reaction
• d.all of the choices

When the equation below is balanced, the coefficient in front of carbon dioxide is C₃H₈ + O₂ -> CO₂ + H₂O:

• a.1
• b.12
• c.3
• d.6