Question

the vapour density of an alkyne is 20. The number of H atom in that alkyne is(Ans:4)

Answer 1

If the answer is 4 then the alkyne is propyne its formula is c3h4

Answer 2

Answer:

4 atoms

Explanation:

For alkyne, the general formula of a compound is

C(n)H(2n-2)

Molecular weight = 2 × vapour density

= 2×20

= 40

C(n)H(2n-2) = 40

12 ×n + 1 × (2n-2) = 40

12n + 2n -2 = 40

14n = 40 + 2

n = 42 / 14

n = 3

Therefore,

no. of H atoms

= 2n - 2

= 2× 3 - 2

= 6-2

= 4