The elements A and B form a compound that contains 60% A and 40% B by mass. The atomic mass of
B is twice that of A. Find the empirical formula of compound
Answers
Answer:
Explanation:
empirical formula
=
C
H
2
.
molecular formula
=
C
6
H
12
Explanation:
AS with all these problems, we assume (for simplicity)
100
⋅
g
of unknown compound.
And thus there are
85.7
%
×
100
⋅
g
12.011
⋅
g
⋅
m
o
l
−
1
with respect to carbon, i.e.
7.14
⋅
m
o
l
⋅
C
And
14.3
%
×
100
⋅
g
1.00794
⋅
g
⋅
m
o
l
−
1
with respect to hydrogen, i.e.
14.1
⋅
m
o
l
⋅
H
.
And thus the
empirical formula
, the simplest whole number ratio that defines constituent elements in a species is
C
H
2
.
Now the
molecular formula
is alway a whole number multiple of the
empirical formula
:
empirical formula
×
n
=
molecular formula
So
(
12.011
⋅
g
⋅
m
o
l
−
1
+
2
×
1.00794
⋅
g
⋅
m
o
l
−
1
)
×
n
=
84
⋅
g
⋅
m
o
l
−
1
.
So
n
=
6
, and
molecular formula
=
6
×
C
H
2
=
C
6
H
12
Answer:
Explanation:
Answer is AB2