At the same temperature and pressure, a gaseous hydride contains twice of its own volume of hydrogen. Vapour density of the hydride is 14. what is its molecular formula?

Explanation

Let, at the same temperature and pressure, 2 volume of hydrogen is present in 1 volume of hydride.
According to Avogadro's hypothesis, at same temperature and pressure if n no. of molecules are present in 1 volume of hydride, the no. of hydrogen molecules in this hydride is 2n.
`therefore` 4 hydrogen atoms or 2 molecules of hydrogen are present.
in 1 hydride molecule [`because` hydrogen is diatomic]
Let, the number of carbon atoms in a hydride molecule be x. therefore, molecular formula of the hydride is `C_(x)H_(4)`.
Molecular mass of the hydride`=2xx14=28`
Now, molecular mass of `C_(x)H_(4)=12x+4`
Therefore, `12x+4=28 or, x=2`
`therefore` Molecular formula of the hydride `C_(2)H_(4)`.