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Review chemical reactions

Total questions: 50

Worksheet time: 56mins

Name
Class
Date
1.
Balance this equation:
MgCl2 --> Mg4+ Cl2
a)
It's already balanced.
b)
4MgCl2 --> Mg4+ 4Cl2
c)
4MgCl2 --> Mg4+ 5Cl2
2.
Balance this equation:
 2Li + Cl2 -> LiCl
a)
2Li + Cl2 -> 4LiCl2
b)
2Li + Cl2 -> LiCl2
c)
2Li + Cl2 -> 2LiCl
3.
The substances listed on the left side of a chemical equation are the
a)
Products
b)
Coefficients
c)
Precipitates
d)
Reactants
4.
In chemical reactions, what does the principle of conservation of mass mean?
a)
Matter is not created or destroyed.
b)
The total mass of the reactants is greater than the total mass of the products.
c)
The total mass of the reactants is less than the total mass of the products.
d)
Matter is not changed.
5.
How many Hydrogen (H) atoms are in NH3O5
a)
3
b)
4
c)
5
d)
1
6.
Name the part in red:

H2 + O2 -> H2O
a)
Coefficient
b)
Product
c)
Yield
d)
Subscript
7.
Name the part in red:

_2_H2 + _1_O2 -> _2_H2O
a)
Coefficient
b)
Product
c)
Yield
d)
Subscript
8.
Name the part in red:

H2 + O2 -> H2O
a)
Coefficient
b)
Product
c)
Reactant
d)
Subscript
9.
Name the part in red:

H2 + O2 -> H2O
a)
Coefficient
b)
Product
c)
Reactant
d)
Subscript
10.
How many phosphorus atoms are in PO4?
a)
1
b)
2
c)
3
d)
4
11.
Which number should go in the blank?
_ H2 + O2 -> 2 H2O
a)
1
b)
2
c)
3
d)
0
12.
Is the following equation balanced or unbalanced ? 
Al + O2 --> Al2O3
a)
Balanced
b)
Unbalanced
13.
Is the following equation balanced or unbalanced ? 
N2 +3 H2 --> 2NH3
a)
Balanced
b)
Unbalanced
14.
How many hydrogens are in 4H2O?
a)
6
b)
8
c)
2
d)
4
15.
Read the following chemical formula: C6H12O6. How many hydrogen atoms are in the formula?
a)
12
b)
6
c)
4
16.
How many atoms of aluminum are on each side of the following equation: 4Al + 3O2 --> 2Al2 O3
a)
2
b)
6
c)
1
d)
4
17.
What are the coefficient used to balance the equation below?
__Ag2O →__ Ag +___O2
a)
2,4,1
b)
1,1,1
c)
2,1,2
d)
2,2,2
18.
How many Oxygen atoms are in 4H2O?
a)
4
b)
1
c)
0
d)
8
19.
 Balance this equation:

__ Al + __ HCl → __ H
2 + __ AlCl3
a)
2, 6, 3, 2
b)
it is already balanced
c)
4, 12, 3, 4
d)
2, 1, 4, 5
20.
Is this balanced?
Al + O2 → 2Al2O3
a)
Yes
b)
No
21.
What is the right ratio of chemicals for the BCE (Balanced Chemical Equation)?__Na + __H2O --> __NaOH + __H2
a)
2,2 --> 2,1
b)
4,4 --> 4,1
c)
1,2 --> 2,4
d)
1,2 --> 2,1
22.

What is the right ratio of chemicals for the BCE (Balanced Chemical Equation)?

__Ca + __H2O --> __Ca(OH)2 + __H2

a)
2,1 --> 2,1
b)
1,2 --> 1,1
c)
1,2 --> 2,4
d)
1,2 --> 2,1
23.
What is the right ratio of chemicals for the BCE (Balanced Chemical Equation)?__CO + __Fe2O3--> __Fe + __CO2
a)
3,1 --> 2,3
b)
3,2 --> 1,1
c)
3,2 --> 2,4
d)
3,2 --> 2,1
24.
What is the right ratio of chemicals for the BCE (Balanced Chemical Equation)?__CH4 + __O2 --> __CO2+ __H2O
a)
2,1 --> 2,1
b)
1,2 --> 1,1
c)
1,2 --> 1,2
d)
1,2 --> 2,1
25.
What is the right ratio of chemicals for the BCE (Balanced Chemical Equation)?__AgNO3 + __H2S --> __Ag2S+ __HNO3
a)
2,1 --> 1,2
b)
1,2 --> 1,1
c)
1,2 --> 1,2
d)
1,2 --> 2,1
26.
What is a coefficient?
a)
The small number on the right of the chemical symbol.
b)
The large number to the left of a formula.
27.
Which side of a chemical equation is the product side?
a)
Left (before the arrow)
b)
Right (after the arrow)
28.
Which side of a chemical equation is the reactant side?
a)
Left (before the arrow)
b)
Right (after the arrow)
29.
Which problem is balanced?
a)
PbO2 + 2H2
b)
SO2 + H20 --> H2SO4
c)
2Na + 2H2O --> 2NaOH + H2
30.
Is the equation balanced?: 2H2O + O2 --> 4MgO + 3Fe
a)
Yes
b)
No
31.
What does the Law of Conservation of Mass state?
a)
Matter cannot be gained or lost in a chemical reaction.
b)
Matter can only be lost in a chemical reaction.
c)
Matter can only be gained in a chemical reaction.
d)
Matter can be gained and lost in a chemical reaction. 
32.
Is this balanced?...
Fe + S --> FeS
a)
YES!
b)
NO!
33.
Balance this equation-
__P4 + __O2 --> __P2O3
a)
it is already balanced
b)
2, 1, 3
c)
1, 2, 3
d)
1, 3, 2
34.
4Si + S8 --> 2Si2S4
a)
Synthesis
b)
Decomposition
c)
Single displacement
d)
Double displacement
35.
2Pb(NO3)2 --> 2PbO + 4NO2 + O2
a)
Synthesis 
b)
Decomposition
c)
Single displacement
d)
Combustion
36.
3Mg + N2 --> Mg3N2
a)
Synthesis 
b)
Decomposition
c)
Single displacement
d)
Combustion
37.
2NO2 --> N2 + 2O2
a)
Synthesis
b)
Decomposition
c)
Single displacement
d)
Combustion
38.
P4 + 3O2 --> 2P2O3
a)
Synthesis 
b)
Decomposition
c)
Single displacement
d)
Combustion
39.
Which reaction type is the following: C5H10O4 + O2 --> CO2 + H2O
a)
Decomposition
b)
Single Replacement
c)
Combustion
d)
Double Replacement
40.
Which of the following is the general formula for a decomposition reaction?
a)
A + B  → AB
b)
AB → A + B
c)
AB + C → AC + B
d)
AB + CD → AC + BD
41.
What coefficient should be used to make the following equation balanced?
N2+O2--> _NO 
a)
1
b)
2
c)
3
d)
4
42.
Always starts with a Hydrocarbon that reacts with oxygen and produces carbon dioxide and water. 
a)
Decomposition
b)
Synthesis
c)
Combustion
d)
Single Replacement
43.
Two Reactants and One Product
a)
Decomposition
b)
Synthesis
c)
Combustion
d)
Single Replacement
44.
C4H12 + O2 → CO2 + H2O
a)
Synthesis
b)
Combustion
c)
Single Replacement
d)
Double Replacement
45.
2Pb(NO3)2   -->   2PbO +  4NO2  +  O2
a)
Synthesis
b)
Decomposition
c)
Single Displacement
d)
Combustion
46.
3Mg + N2 --> Mg3N2
a)
Synthesis 
b)
Decomposition
c)
Single displacement
d)
Combustion
47.
2NO2 --> N2 + 2O2
a)
Synthesis
b)
Decomposition
c)
Single displacement
d)
Combustion
48.

Reaction:


2 KClO3 --> 2 KCl + 3 O2


If 200 g of oxygen and 300 g of KCl is formed, how much KClO3 reachted in the first place?

(a)  

49.

Reaction: N2 + 3 H2 --> 2 NH3

If 25 g of nitrogen gas reacts with 5 gram of hydrogen gas, how much NH3 is formed?

a)

30 g

b)

17 g

c)

40 g

d)

20 g

50.

Reaction: H2O2 → H2O + O2


If 400 g of H2O2 decomposes, and 150 g of water is formed. How much oxygen was produced in this reaction?

a)

400 g

b)

150 g

c)

250 g

d)

550 g