Unit 1 | Lessons 9 - 11 | Chemical Equations and Balancing

Question 1

What are elements that react together called?

Answer 1

Reactants

Question 2

What are elements created by a chemical reaction called?

Answer 2

Products

Question 3

Definition of:
Exothermic reaction

Answer 3

A chemical reaction in which energy is released

Question 4

True or False:
Energy given off in an Exothermic reaction can only be heat

Answer 4

False:
Energy released in an Exothermic reaction can be either heat, light, or electricity

Question 5

Definition of:
Endothermic reaction

Answer 5

A chemical reaction in which energy is absorbed

Question 6

What is the law of conservation of mass

Answer 6

The total mass of substances in a reaction is equal to the mass of the substances after the reaction

Question 7

What is a “skeleton equation”?

Answer 7

A chemical equation that isn’t balanced

Question 8

What are the five kinds of chemical reactions?

Answer 8

1. Synthesis/Formation
2. Decomposition
3. Single replacement
4. Double replacement
5. Combustion

Question 9

What is a Synthesis/Formation chemical reaction?

Answer 9

When 2 elements react to make one compound:
A + B = AB

Question 10

What is a Decomposition chemical reaction?

Answer 10

When a compound breaks down into 2 elements
AB = A + B

Question 11

What is a Single replacement chemical reaction?

Answer 11

When an element reacts with an ionic compound to produce a new compound and separate the cation from the anion:
A + BC = AC + B

Question 12

What is a Double replacement chemical reaction

Answer 12

When two compounds react together and “switch partners”:
AB + XY = AY + XB
(A and X are always positive)