Question

Find the Empirical formula of the organic compound from the data given below
Carbon-75 92%, Hydrogen 632, Nitrogen - 17.78.
atomic Weight of C-12, H-1,N-14​

Answer 1

Explanation:

SymbolPercentage

At. Weight

Relative ratio

Simplest ratioC

H

N75.92%

6.32%

17.76%12

1

141275.92=6.32

16.32=6.32

1417.76=1.26

1.266.32=5

1.266.32=5

1.261.26=1

Empirical Formula ⇒C5H5N

Vapour density =39.5

Molecular Mass =2×V.D.

=2×39.5=79

Empirical formula Mass =12×5+5×1+1×14

=60+5+14

=79

n=Empirical formula massMolecular formula mass=7979 

Thus, both Empirical formula and Molecular formula are C5H5N.

Answer 2

Element. %

______________________________________

C. 75.92 75.92 6.32

______ = _____ =5

12. 1.26

______________________________________

H. 6.32 6.32 6.32

____= ____. =5

1. 1.26

______________________________________

N. 17.76 70.76 1.26

_____= _____=5

14 1.26

__________________________________

Empitical formula;. -C5H5N

molevular weight=2×Vapour Density

=2×39.5

=79

Empricsl formul weight=C×5+H×5+N×1

=12×5+1×5+14×1

=16+5+14

=79

n= Molecular weight

_______________________

Empirical formula weight

Molecular formula =Empirical formula=C5H5N