WorksheetsCounting Atoms
Total questions: 25
Worksheet time: 32mins
Name
Class
Date
1.
Is this balanced?...
Al + O2 --> 2Al2O3
Al + O2 --> 2Al2O3
a)
Yes!
b)
NO!
2.
Balance this equation...
Sb2S3 + O2 --> Sb + SO2
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!
3.
Balance this equation-
__P4 + __O2 --> __P2O3
__P4 + __O2 --> __P2O3
a)
it is already balanced
b)
2, 1, 3
c)
1, 2, 3
d)
1, 3, 2
4.
Balance this equation
_N2 + _H2 --> _NH3
_N2 + _H2 --> _NH3
a)
1,2,3
b)
1,3,2
c)
1,1,2
d)
2,1,1
5.
Balance this equation.
_Mg + _Cl2 --> _MgCl2
_Mg + _Cl2 --> _MgCl2
a)
1, 2,1
b)
already balanced
c)
2,1,1
d)
1,1,2
6.
Balance this equation.
_SnO2 +_H2-->_Sn +_H2O
_SnO2 +_H2-->_Sn +_H2O
a)
1,1,2,1
b)
1,2,1,1
c)
1,2,1,2
d)
1,2,2,1
7.
Balance this equation-
_SeCl6+_O2>_SeO2+_Cl2
_SeCl6+_O2>_SeO2+_Cl2
a)
1,2,1,2
b)
1,1,1,3
c)
1,2,1,1
d)
2,1,1,1
8.
Balance this equation
_Zn+_HCl-->_ZnCl2 +_H2
_Zn+_HCl-->_ZnCl2 +_H2
a)
1,1,2,1
b)
1,1,1,2
c)
1,2,1,1
d)
2,1,1,1
9.
Balance this equation
_Al +_HCl --> _H2 +_AlCl3
_Al +_HCl --> _H2 +_AlCl3
a)
2, 6, 3, 2
b)
it is already balanced
c)
4, 12, 3, 4
d)
2, 1, 4, 5
10.
The substances at the beginning of a chemical equation are called the ____
a)
product
b)
yield
c)
chemical symbol
d)
reactants
11.
How many O's are in Al₂(SO₄)₃
a)
4
b)
12
c)
7
d)
24
12.
Number of H in 3(NH₄)₂CrO₄
a)
4
b)
2
c)
8
d)
24
13.
The red numbers in the image below represent ________
a)
subscripts
b)
coefficients
c)
I don't know, and don't want to try
d)
None of the answers are correct
14.
The blue numbers in the image below represent ________
a)
I don't know, and don't want to try
b)
coefficients
c)
subscripts
d)
none of the answers are correct
15.
In the equation, 2Mg + O2 ---> 2MgO, which are the reactants?
a)
Mg and O
b)
MgO
c)
Mg and MgO
d)
O and MgO
16.
In a chemical reaction, everything to the rightof the arrow is called ______________.
a)
Products
b)
Yields
c)
Molecules
d)
Reactants
17.
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
18.
Is the following equation balanced or unbalanced?
Fe + S --> FeS
Fe + S --> FeS
a)
balanced
b)
unbalanced
19.
Two elements react to form one product is an example of which type of chemical reaction?
a)
combustion
b)
decomposition
c)
synthesis
d)
single replacement
20.
Which type of reaction takes place in the presence of oxygen and produces carbon dioxide and water?
a)
double replacement
b)
decomposition
c)
combustion
d)
single replacement
21.
What kind of reaction is this:
4Fe + 3O2 → 2Fe2O3
4Fe + 3O2 → 2Fe2O3
a)
Synthesis
b)
Decomposition
c)
Single Replacement
d)
Double Replacement
22.
What kind of reaction is this:
2H2O2 →2 H2O + O2
2H2O2 →2 H2O + O2
a)
Synthesis
b)
Decomposition
c)
Single Replacement
d)
Combustion
23.
What kind of reaction is this:
2C3H7OH +9O2 -> 6CO2 + 8H2O
2C3H7OH +9O2 -> 6CO2 + 8H2O
a)
Double Replacement
b)
Combustion
c)
Single Replacement
d)
Decomposition
24.
What kind of reaction is this:
Fe + CuSO4 -> Cu + FeSO4
Fe + CuSO4 -> Cu + FeSO4
a)
Double Replacement
b)
Decompostion
c)
Single Replacement
d)
Combustion
25.
The reaction below is an example of?
AgNO3 + NaCl → AgCl + NaNO3
AgNO3 + NaCl → AgCl + NaNO3
a)
Single Replacement
b)
Double Replacement
c)
Decomposition
d)
Combustion
100 %
