10.34.R - Lesson Review: Balancing Equations / Types of Chemical Reactions

Question 1

The number in front of the molecule that tells you how many molecules you are working with is called the _____________.
reactant
product
subscript
coefficient

Answer 1

coefficient

Question 2

Is this equation balanced or unbalanced?
H2 + O2 = H20

the equation is balanced
the equation is unbalanced, and the correct balance would be 2H2 + O2 = 2H2O
the equation is unbalanced, and the correct balance would be 2H2 + 2O2 = H2O
the equation is unbalanced, and the correct balance would be 2H2 + 2O2 = 2H2O

Answer 2

the equation is unbalanced, and the correct balance would be 2H2 + O2 = 2H2O

Question 3

Is this equation balanced or unbalanced?
CH4 + Cl2 -> CCl4 + HCl

the equation is unbalanced, and the correct balance would be CH4 + 4Cl2 –> CCl4 + 4HCl
the equation is unbalanced, and the correct balance would be CH4 + 4Cl2 –> 2CCl4 + 4HCl
the equation is unbalanced, and the correct balance would be 2CH4 + 4Cl2 –> CCl4 + 4HCl
the equation is balanced

Answer 3

the equation is unbalanced, and the correct balance would be CH4 + 4Cl2 –> CCl4 + 4HCl

Question 4

Is this equation balanced or unbalanced?
C + O2 = C02

the equation is balanced
the equation is unbalanced, and the correct balance would be 2C + O2 = 2CO2
the equation is unbalanced, and the correct balance would be 2C + O2 = CO2
the equation is unbalanced, and the correct balance would be C + 2O2 = CO2

Answer 4

the equation is balanced

Question 5

Is this equation balanced or unbalanced?
Fe + Cl2 -> FeCl3

the equation is unbalanced, and the correct balance would be 2Fe + Cl2 –> 2FeCl3
the equation is unbalanced, and the correct balance would be 2Fe + 3Cl2 –> 2FeCl3
the equation is balanced
the equation is unbalanced, and the correct balance would be 3Fe + 2Cl2 –> 2FeCl3

Answer 5

the equation is unbalanced, and the correct balance would be 2Fe + 3Cl2 –> 2FeCl3

Question 6

Match each of the following equations to the reaction that it is showing:
AB + C –> A + BC

single-replacement reaction
decomposition reaction
double-replacement reaction
synthesis reaction
combustion

Answer 6

single-replacement reaction

Question 7

Match each of the following equations to the reaction that it is showing:

BC –> B + C

single-replacement reaction
decomposition reaction
double-replacement reaction
synthesis reaction
combustion

Answer 7

decomposition reaction

Question 8

Match each of the following equations to the reaction that it is showing:

AB + CD –> CB + AD

single-replacement reaction
decomposition reaction
double-replacement reaction
synthesis reaction
combustion

Answer 8

double-replacement reaction

Question 9

Match each of the following equations to the reaction that it is showing:

A + B –> AB

single-replacement reaction
decomposition reaction
double-replacement reaction
synthesis reaction
combustion

Answer 9

synthesis reaction

Question 10

Match each of the following equations to the reaction that it is showing:

Compound + Oxygen –> Oxide + Heat

single-replacement reaction
decomposition reaction
double-replacement reaction
synthesis reaction
combustion

Answer 10

combustion

Question 11

Which reaction is the following equation showing?
AB + C -> A +BC

double-replacement reaction
single-replacement reaction
synthesis reaction
combustion reaction
decomposition reaction

Answer 11

single-replacement reaction

Question 12

Which combustion equation violates the law of conservation of matter?

2C8H18 + 25O2 –> 16CO2 + 18H2O
2C6H14 + 19O2 –> 12CO2 + 14H2O
CH4 + 2O2 –> CO2 + 2H2O
C3H8 + 6O2 –> 3CO2 + 4H2O

Answer 12

C3H8 + 6O2 –> 3CO2 + 4H2O

Question 13

A _________________ reaction is when oxygen combines with another compound to form water and carbon dioxide.
single-replacement
decomposition
combustion
synthesis
double-replacement

Answer 13

combustion

Question 14

Fe(s) + CuSO4(aq) –> FeSO4(aq) + Cu(s)

This chemical equation represents a ______________ reaction.

decomposition
double-replacement
synthesis
single-replacement

Answer 14

single-replacement

Question 15

A reaction in which two or more substances combine to form a new substance is called a ______________.
double-replacement reaction
decomposition reaction
single-replacement reaction
combustion reaction
synthesis reaction

Answer 15

synthesis reaction

Question 16

What is the difference between an exothermic and an endothermic reaction? Please respond in 1–2 complete sentences using your best grammar.

Answer 16

Your Answer:
An exothermic reaction is where heat is released. An endothermic reaction is where heat is absorbed, causing a cooling effect on the surrounding environment.