Question

8
An organic dibasic acid contains
C- 17.39% H=1.45%, Br = 57.979
The vopour density of the acid
is 138. calculate the empirical
and molecular formula of the
acid (At. Wt. Br=80,(-12, 0=16, H=1)​

Answer 1

Answer:

C

2

H

2

O

4

C:H:O=

12

26.7

:

1

2.2

:

16

71.1

=1:1:2

empirical formula is CHO

2

Mol. mass of diethyl ester= 2×72 =146u

Formula mass of ethyl group (−CH

2

)= 29u

In diethyl ester two ethyl group must have replaced the H atoms of dibasic acid

The mol. mass of acid =146−(2×29)+2=90 u

Molecular formula of acid=

45

90

×CHO

2

=C

2

H

2

O

4