Worksheets8C Percent Composition
Total questions: 9
Worksheet time: 16mins
Name
Class
Date
1.
What is the percent composition of oxygen in MgO?
a)
20%
b)
40%
c)
50%
d)
60%
2.
What is the percent composition of sodium in NaCl?
a)
39%
b)
61%
c)
35%
d)
65%
3.
What is the percent composition of sulfur in the compound MgSO4?
a)
20%
b)
27%
c)
46%
d)
53%
4.
What is the percent composition of Benzene, C6H6?
a)
C = 50%
H = 50%
H = 50%
b)
C = 85.7 %
H = 14.3%
H = 14.3%
c)
C = 92.2%
H = 7.8%
H = 7.8%
d)
C = 71.9%
H = 28.1%
H = 28.1%
5.
What is the percent composition by mass of sulfur in the compound MgSO4 (gram formula mass = 120 g/mol)?
a)
20%
b)
27%
c)
46%
d)
53%
6.
In which compound is the percent composition by mass of Cl equal to 42%?
a)
HClO (gram formula mass = 52 g/mol)
b)
HClO2 (gram formula mass = 68 g/mol)
c)
HClO3 (gram formula mass = 84 g/mol)
d)
HClO4 (gram formula mass = 100 g/mol)
7.
What percentage of the total atomic mass of calcium nitrate (Ca(NO3)2) is composed of nitrogen? Hint - another way to think of calcium nitrate is Ca(NO3)(NO3).
a)
17%
b)
24%
c)
29%
d)
59%
8.
What percentage of the total atomic mass of lithium phosphide (Li3P) is composed of phosphorus?
a)
13%
b)
29%
c)
40%
d)
60%
9.
What percentage of the total atomic mass of lithium phosphide (Li3P) is composed of lithium? Hint - consider all three atoms of lithium in your calculation.
a)
13%
b)
29%
c)
40%
d)
60%
100 %
