Chemical equations Retake
Name:
1.
Date:
Which is an example of a chemical reaction?
A. nails rusting
B. glass melting
C. sugar dissolving
D. alcohol vaporizing
4.
Which of the following is a balanced equation for
the combustion of ethanol (CH3 CH2 OH)?
A. CH3 CH2 OH + 3O2 ! CO2 + 2H2 O
B. CH3 CH2 OH + 3O2 ! 2CO2 + 3H2 O
C. CH3 CH2 OH + O2 ! 2CO2 + 3HO
D. CH3 CH2 OH + 2O2 ! 3CO2 + 2H2 O
2.
NH3 (g) +
N2 (g) +
O2 (g) !
H2 O(g)
When the reaction above is completely balanced,
the coe cient for NH3 will be
A. 2.
B. 3.
C. 4.
D. 6.
5.
3.
C3 H8 + O2 ! CO2 + H2 O
This chemical equation represents the combustion
of propane. When correctly balanced, the
coe cient for water is
Hydrazine, N2 H4 , and dinitrogen tetroxide, N2 O4 ,
react to form gaseous nitrogen and water. Which
of these represents a properly balanced equation
for this reaction?
A. 2.
A. N2 H4 + N2 O4 ! N2 + H2 O
B. 2N2 H4 + N2 O4 ! 2N2 + 4H2 O
C. 2N2 H4 + N2 O4 ! 3N2 + 4H2 O
D. 2N2 H4 + 3N2 O4 ! 5N2 + 6H2 O
page 1
B. 4.
C. 8.
D. 16.
6.
8.
The reaction of element X ( ) with element Y
(O) is represented in the following diagram:
In making a pizza, which process involves a
chemical change?
A. mixing spices for the sauce
B. slicing pepperoni for the topping
C. spreading cheese on the pizza
D. baking the dough to form the crust
Which equation properly describes the reaction
between X and Y?
A. 3X + 8Y ! X3 Y8
B. 3X + 6Y ! X3 Y6
C. X + 2Y ! XY2
9.
D. 3X + 8Y ! 3XY2 + 2Y
In the chemical reaction shown below, all of the
HCl and Zn will react to form H2 and ZnCl2 .
Which of the following statements describes the
result of this reaction?
A. The hydrogen gas will have a mass of zero.
B. The zinc chloride will have less mass than the
zinc.
7.
C. The mass of the products will equal the mass
of the reactants.
2Na(s) + Cl2 (g) ! 2NaCl(s)
s = solid
D. The mass of the hydrogen atoms will decrease
in the products.
g = gas
The equation represents a chemical change because
.
A. it is balanced
10.
B. the product is solid
C. a new substance is produced
Copper in the compound CuSO4 can be isolated
in the following reaction with iron.
Fe + CuSO4 ! FeSO4 + Cu
D. there are two substances on the reactant side
What type of reaction is shown above?
page 2
A. decomposition
B. synthesis
C. single displacement
D. double displacement
Chemical equations Retake
11.
Potassium carbonate (K2 CO3 ) is an important
component of fertilizer. The partially balanced
equation for the reaction of 6 moles of potassium
hydroxide (KOH) and 3 moles of carbon dioxide
(CO2 ) to produce potassium carbonate and water
is given below.
6KOH + 3CO2 !
14.
The gure below represents a reaction.
K2 CO3 + 3H2 O
When this equation is balanced, what is the
coe cient for potassium carbonate?
A. 2
12.
B. 3
C. 6
D. 9
What type of reaction is shown?
A. synthesis
B. decomposition
C. single displacement
D. double displacement
Which of the following chemical reactions is a
decomposition reaction?
A. BaCO3 ! BaO + CO2
B. 2Ca + O2 ! 2CaO
C. 3Br2 + 2FeI3 ! 2FeBr3 + 3I2
D. MgCl2 + H2 SO4 ! MgSO4 + 2HCl
15.
Which of the following chemical equations is
balanced correctly?
A. C6 H6 + O2 ! 2CO2 + 3H2 O
B. CS2 + 3Cl2 ! CCl4 + S2 Cl2
13.
C. B2 O3 + 2C ! B4 C + CO
An unbalanced chemical equation is shown below.
H3 BO3 (
+
B2 O3 +
D. Cl2 + NaI ! 2NaCl + I2
H2 O
What are the coe cients of the balanced equation?
A. 2 : 1 : 3
B. 2 : 2 : 3
C. 3 : 1 : 2
D. 3 : 2 : 2
page 3
Chemical equations Retake
16.
When pure N2 O5 is heated under certain
conditions, O2 and NO2 are produced. What type
of reaction is this?
19.
Ca + 6B ! CaB6
A. combustion
Which type of reaction is shown by this equation?
B. decomposition
C. double displacement
D. synthesis (combination)
17.
Calcium and boron react to form calcium boride,
as represented by the chemical equation below.
Which of the following equations represents the
law of conservation of mass?
20.
A. H2 O ! H2 + O2
A. combination
B. decomposition
C. double displacement
D. single displacement
The following chemical equation shows the
incomplete formula for burning methanol. The
question mark represents the unknown number of
oxygen (O2 ) molecules.
2CH3 OH+?O2
B. 2H + 2O ! 2H2 O
How many molecules of O2 are needed to balance
this chemical equation?
C. 2H2 O ! 2H2 + O2
D. H2 + O2 ! H2 O + H2 O2
A. 1
18.
> 2CO2 + 4H2 O
The white pigment in many paints is titanium
dioxide (TiO2). It is made by burning titanium(IV)
chloride. The other product in this reaction is
chlorine gas.
21.
What is the balanced equation for this reaction?
B. 3
C. 5
D. 6
Which equation represents a single replacement
reaction that can occur?
A. F2 + 2NaCl ! 2NaF + Cl2
A. TiCl4 + O2 ! TiO2 + 2Cl2
B. Cl2 + 2NaF ! 2NaCl + F2
B. 2TiCl4 + O2 ! TiO2 + 4Cl
C. Cu + 2NaCl ! CuCl2 + 2Na
C. TiCl4 + 2O2 ! 2TiO2 + Cl2
D. Zn + 2NaF ! ZnF2 + 2Na
D. 2TiCl4 + 2O2 ! 2TiO2 + Cl4
page 4
Chemical equations Retake
22.
Which pair of substances will likely undergo a
single replacement reaction?
A. Na and BaCl2
B. Zn and BaCl2
C. Ca and BaCl2
D. K and BaCl2
24.
Which model demonstrates the Law of
Conservation of Matter?
A.
B.
C.
23.
Which remains the same during a chemical
reaction?
A. the temperature of the elements
D.
B. the total number of atoms
C. the total number of compounds
25.
What coe cients are required to balance this
equation?
Fe2 O3 +
page 5
CO !
Fe +
A. 2, 6, 3, 6
B. 1, 3, 2, 3
C. 1, 1, 2, 2
D. 1, 1, 2, 1
CO2
Chemical equations Retake
Problem-Attic format version 4.4.693
c 2011–2024 EducAide Software
_
Licensed for use by Yerbol Mukhamadiyev
Terms of Use at www.problem-attic.com
Chemical equations Retake
3/27/2025
14.
Answer:
Objective:
Points:
A
MA 5.2
1
15.
Answer:
Objective:
Points:
B
MA 5.1
1
16.
Answer:
Objective:
Points:
B
MA 5.2
1
B
1
6.
Answer:
Points:
17.
Answer:
Objective:
Points:
C
MA 5.1
1
1
7.
Answer:
Points:
C
1
18.
Answer:
Objective:
Points:
A
MA 5.1
1
8.
Answer:
Objective:
Points:
D
MA 10
1
19.
Answer:
Objective:
Points:
A
MA 5.2
1
9.
Answer:
Objective:
Points:
C
MA 4
1
20.
Answer:
Objective:
Points:
B
MS 2a1
1
10.
Answer:
Objective:
Points:
C
MA 5.2
1
21.
Answer:
Objective:
Points:
A
5.01
1
11.
Answer:
Objective:
Points:
B
MA 5.1
1
22.
Answer:
Points:
D
1
12.
Answer:
Objective:
Points:
23.
Answer:
Points:
B
1
A
MA 5.2
1
24.
Answer:
Points:
A
1
MA 1.1
1
25.
Answer:
Objective:
Points:
B
5.02
1
1.
Answer:
Points:
A
1
2.
Answer:
Points:
C
1
3.
Answer:
Points:
C
1
4.
Answer:
Points:
B
1
5.
Answer:
Points:
13.
Answer:
Objective:
Points: