Chemical Reactions and Equations
Practice Test
1.
A number placed before a formula to indicate how many units of the substance are involved in a chemical reaction is called a ____________.
a.
coefficient
b.
substrate
c.
superscript
d.
subscript
2.
In a ______________ reaction, two or more substances react to form a single product.
a.
synthesis
b.
gas-producing
c.
decomposition
d.
double displacement
3.
Changes in energy, color, and odor are indications that a _____________ has taken place.
a.
precipitation reaction
b.
chemical reaction
c.
displacement reaction
d.
separation reaction
4.
What type of reaction is represented by the equation CH
4
+ 2O
2
CO
2
+ 2H
2
O?
a.
synthesis
b.
decomposition
c.
double displacement
d.
combustion
5.
A ____________ reaction is one in which one element takes the place of another in a compound.
a.
decomposition
b.
double displacement
c.
single displacement
d.
synthesis
6.
This type of chemical reaction has energy written as a product.
a.
light-absorbing
b.
energy-absorbing
c.
exothermic
d.
endothermic
7.
Changes in an equilibrium system can be described according to _____________ principle.
a.
Dalton's
b.
Boyle's
c.
Le Chatelier's
d.
Rutherford's
8.
A description of a chemical reaction that includes the names of all reactants and products, but not the formulas, is called a ___________________.
a.
word equation
b.
balanced equation
c.
chemical equation
d.
skeleton equation
9.
________________ indicate a state of equilibrium in a chemical equation.
a.
Double reaction arrows
b.
A minus sign
c.
A plus sign
d.
An equal sign
10.
A solid that forms from a solution during a chemical reaction is called a ______________.
a.
formate
b.
precipitate
c.
reactant
d.
substrate
11.
A system is said to be in ___________ when no net change in the amounts of reactants and products occurs.
a.
state
b.
equilibrium
c.
reverse
d.
dislacement
12.
The substances to the left of the reaction arrow are called _______________.
a.
precipitates
b.
products
c.
gases
d.
reactants
13.
A substance that increases the rate of a chemical reaction without being permanently changed or consumed is called ______________.
a.
a reactant
b.
an equilibrate
c.
a catalyst
d.
a product
14.
A reaction between magnesium chloride and silver nitrate yields magnesium nitrate and silver chloride. What is the coefficient for magnesium nitrate in the balanced equation for the reaction?
a.
2
b.
1
c.
3
d.
4
15.
What type of reaction is represented by the equation 2Fe + 3Cl
2
2FeCl
3
?
a.
decomposition
b.
combustion
c.
synthesis
d.
single displacement
16.
Adding energy to an equilibrium system that is exothermic to the right causes the system to ______________.
a.
shift to the right
b.
slow down
c.
remain unchanged
d.
shift to the left
17.
Reactions that can occur in either direction are said to be ____________.
a.
backward
b.
limited
c.
reversible
d.
forward
18.
The substances to the right of the reaction arrow are called _______________.
a.
products
b.
precipitates
c.
gases
d.
reactants
19.
Will the double displacement reaction NaOH + CaBr2 occur? If so, what is the product of the reaction?
a.
No
b.
Yes, CaNa
c.
Yes, Br(OH)2
d.
Yes, Ca(OH)2
20.
Adding reactants causes an equilbrium to ______________.
a.
shift to the left
b.
shift to the right
c.
shift in both directions simultaneously
d.
remain unchanged
21.
Which of the following single-replacement reactions will occur?
a.
Cu(s) + ZnCl2(aq) [arrow]
b.
Br2(g) + HF(aq) [arrow]
c.
Cl2(g) + HBr(aq) [arrow]
d.
Au(s) + Cu(NO3)2 (aq) [arrow]
22.
What type of reaction is represented by the equation Pb(NO
3
)
2
+ K
2
CrO
4
PbCrO
4
+ 2KNO
3
?
a.
single displacement
b.
double displacement
c.
decomposition
d.
synthesis
23.
What is the missing product in this balanced equation describing the decomposition of water? 2H
2
O(l) + energy
O
2
(g) +
a.
H
2
(g)
b.
H
2
O(g)
c.
energy
d.
2H
2
(g)
24.
The positive and negative portions of two ionic compounds are interchanged in this type of reaction.
a.
decomposition
b.
synthesis
c.
double displacement
d.
single displacement
25.
Activation energy is the energy required to _________________.
a.
slow down a reaction
b.
stop a reaction
c.
initiate a reaction
d.
speed up a reaction
26.
What type of reaction occurs when potassium and chlorine gas produce potassium chloride?
a.
synthesis
b.
replacement
c.
combustion
d.
decomposition
27.
A ____________ reaction is one in which a compound breaks down into two or more simpler substances.
a.
replacement
b.
synthesis
c.
photosynthesis
d.
decomposition
28.
What is the coefficient for NaOH in the equation that describes its reaction with CO
2
to produce Na
2
CO
3
and H
2
O?
a.
3
b.
2
c.
1
d.
4
