Wayground logo

Free Printable Worksheets

Font size

S
M
L
XL
Worksheets

SM -HW: Balancing Chemical Equations

Total questions: 45

Worksheet time: 2hrs 15mins

Name
Class
Date
1.

Complete the sentence.


During a chemical reaction, atoms ________.

a)

can appear

b)

can disappear

c)

get rearranged

d)

stop moving and vibrating

2.

How many iron (Ag) atoms are reactants in this equation?

4Ag + 3O2 → 2Ag2O

a)

4

b)

2

c)

3

d)

0

3.
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. 
4.
Is the following equation balanced?...
Al + O2 --> 2Al2O3
a)
Yes!
b)
No!
5.
What is the number before a chemical formula called?
Ex: 2H2 + O2 --> 2H2O
a)
Coefficient
b)
Subscript
c)
Atom
d)
Equation
6.
Is the following equation balanced?
4Fe + 3O2 --> 2Fe2O3
a)
yes
b)
no
7.
Balance this equation:
MgCl2 --> Mg4+ Cl2
a)
It's already balanced.
b)
4MgCl2 --> Mg4+ 4Cl2
c)
4MgCl2 --> Mg4+ 5Cl2
8.
Balance this equation:
 2Li + Cl2 -> LiCl
a)
2Li + Cl2 -> 4LiCl2
b)
2Li + Cl2 -> LiCl2
c)
2Li + Cl2 -> 2LiCl
9.
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.
10.

How many Hydrogen (H) atoms are in NH3O5

a)

3

b)

4

c)

5

d)

1

11.
Name the part in red:

H2 + O2 -> H2O
a)
Coefficient
b)
Product
c)
Yield
d)
Subscript
12.
Name the part in red:

H2 + O2 -> H2O
a)
Coefficient
b)
Product
c)
Reactant
d)
Subscript
13.
Name the part in red:

H2 + O2 -> H2O
a)
Coefficient
b)
Product
c)
Reactant
d)
Subscript
14.

Which number should go in the blank?

___ H2 + O2 -> 2 H2O

a)

1

b)

2

c)

3

d)

0

15.
Is the following equation balanced or unbalanced ? 
Al + O2 --> Al2O3
a)
Balanced
b)
Unbalanced
16.
Is the following equation balanced or unbalanced ? 
N2 +3 H2 --> 2NH3
a)
Balanced
b)
Unbalanced
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.
 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
19.
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
20.

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
21.
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
22.
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
23.
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
24.
What is the right ratio of chemicals for the BCE (Balanced Chemical Equation)?__H2 + __S --> __H2S
a)
1,1 --> 1
b)
2,2 --> 2
c)
1,2 --> 1
d)
1,2 --> 2
25.
What is the right ratio of chemicals for the BCE (Balanced Chemical Equation)?__H2SO3 + __KOH--> __H2O+ __K2SO3
a)
2,1 --> 2,1
b)
1,2 --> 1,1
c)
1,2 --> 1,2
d)
1,2 --> 2,1
26.
What is the right ratio of chemicals for the BCE (Balanced Chemical Equation)?__Al + __O2--> __Al2O3
a)
4,1 --> 2
b)
4,3 --> 4
c)
3,4 --> 1
d)
4,3 --> 2
27.
What is the right ratio of chemicals for the BCE (Balanced Chemical Equation)?__MnO2 + __HCl --> __MnCl2 + __H2O __Cl2
a)
4,1 --> 2,1,2
b)
1,2 --> 1,1,4
c)
1,4 --> 1,2,1
d)
1,4 --> 2,2,1
28.
Is this equation balanced?
a)
yes
b)
no
c)
Not enough information
d)
Left side is balanced
29.
Balance this equation...
H2 + Cl2 --> HCl
a)
It is balanced 
b)
3H2 + Cl2 --> 6H2Cl
c)
H2 + Cl2 --> 2HCl
d)
I don't know! Oh well.
30.
Balance this equation...
HgO --> 2Hg + O2
a)
It is balanced 
b)
2HgO --> Hg + O2
c)
2HgO --> 2Hg + O2
d)
I don't know...Oh well!
31.
Balance this equation...
Sb2S3 + O2 --> Sb + SO2
a)
It is balanced
b)
Sb2S3 + 3O2 --> 2Sb + 3SO2
c)
Sb2S3 + O2 --> 2Sb + SO2
d)
I don't know...Oh well!
32.
What coefficient should be used to make the following equation balanced?
N2+O2--> _NO 
a)
1
b)
2
c)
3
d)
4
33.
How many HCl molecules do you need to balance this equation? 
Mg +  __HCl --->  MgCl2 + H2
a)
1
b)
2
c)
3
d)
4
34.
Is this balanced?
Al + O2 → 2Al2O3
a)
Yes
b)
No
35.

Balance this equation

_Al +_HCl --> _H2 +_AlCl3

a)

2,6,3,2

b)

it's already balanced

c)

4,12,3,4

d)

2,1,4,5

36.
What is the total number of atoms present in 5Na3PO4
a)
5
b)
40
c)
55
d)
8
37.

Determine the coefficients to balance the equation.

__Al +__HCl --> __H2 +__AlCl3

a)

2,6,3,2

b)

it's already balanced

c)

4,12,3,4

d)

2,1,4,5

38.

Balance the the following equation.

__Zn+__HCl -->__ZnCl2 +__H2

a)

1,1,2,1

b)

1,1,1,2

c)

1,2,1,1

d)

2,1,1,1

39.
Which number should go in the blank?
Al(NO3)3 + _  NaOH -> Al(OH)3 + 3 NaNO3
a)
1
b)
2
c)
3
d)
0
40.
Which number should go in the blank?
Mn + _ HNO3 → Mn(NO3)2 + H2
a)
1
b)
2
c)
3
d)
0
41.
The numbers needed to balance the equation are:
a)
1, 1, 1, 2
b)
1, 1, 2, 2
c)
1, 1, 1, 1
d)
2, 3, 1, 3
42.
The numbers needed to balance the equation are:
a)
2, 7, 6, 4
b)
2, 1, 3, 2
c)
1, 1, 3, 2
d)
2, 3, 1, 3
43.
The numbers needed to balance the equation are:
a)
2, 7, 6, 4
b)
2, 1, 3, 2
c)
3, 1, 1, 3
d)
2, 3, 1, 3
44.

Balance this equation, CaCO3(s) → CaO(s) + CO2(g)?

a)

3,1,2

b)

1,1,1

c)

1,3,1

d)

2,6,3

45.

Balancing this Equation,

____ Fe + ____ Cl2 → ____ FeCl3

a)

1, 2 → 2

b)

2, 2 → 2

c)

2, 3 → 2

d)

3, 3 → 2