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Empirical and molecular formula, percentage composition
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Single correct option
Difficulty 1 of 3
mc021
A hydrocarbon has empirical formula
CH
and molar mass
78
g
mo
l
−
1
(C = 12, H = 1). Its molecular formula is:
A
C
X
8
H
X
8
B
C
X
6
H
X
6
C
C
X
2
H
X
2
D
C
X
4
H
X
4
Answer: B
Empirical formula mass
=
13
.
n
=
78/13
=
6
, so the molecular formula is
(
CH
)
6
=
C
X
6
H
X
6
.
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