Question

11. An organic compound contains C, H and O elements
1.8 g of the compound on combustion gave 2.64 g of
carbon dioxide and 1.08 g of water. Obtain the
empirical formula of the compound.​

Answer 1

empirical formula of CHO is CH2O

Answer 2

Answer:

Empirical formula= CH2O

Explanation:

Given an organic compound of 1.8gm

On combustion 2.64gm of CO2 and 1.08gm of H2O,

The molecular weight of CO2 is 44gm, therefore it has 12gm of Carbon in it.

2.64gm CO2= (12/44) x 2.64 = 0.72gm

The molecular weight of H2O is 18gm, therefore it has 2gm of H20.

1.08gm H20= (2/18) x 1.08= 0.12gm

Percentage of C = (0.72/1.8) x 100 = 40%

Percentage of H = (0.12/1.8) x 100= 6.66%

Percentage of O = 100- (40+6.66)= 53.34%

Therefore the atomic weight of C is 12gm, percentage/weight= 40/12= 3.33

The atomic weight of H is 1, percentage/weight= 6.66/1 = 6.66

The atomic weight of O is 16gm, percentage/weight= 53.34/16= 3.33

Hence C= 3.33, H=6.66 and O=3.33

Least ratio= C= 3.33/3.33= 1

H= 6.66/3.33= 2

O= 3.33/3.33=1

Therefore 1 molecule of C, 2 molecules of H and 1 molecule of O= CH2O