A compound contains 32% carbon, 4% hydrogen and rest oxygen. Its vapour density is 75. Calculate the empirical and molecular formula.

Explanation

Empirical formula . = `C_(2)H_(3)O_(3)`
Empirical formula mass = 24+ 3 +48 = 75
Molecular mass = 2 `xx` Vapour density
= `2xx75`
= 150
n = `("Molecular mass")/("Empirical formula mass") = 150/75 =`2
`:.` Molecular formula = `(Empirical formula)_(n)`
`:.` Molecular formula = `C_(2)H_(3)O_(3) xx 2`
Molecular formula = `C_(4)H_(6)O_(6)`