Question

A compound contains 0.5 mole of sodium , 0.5 mole of nitrogen , and 1.0 mole of hydrogen . The empirical formula of the compound is

A NaNH

B Na2NH

C NaNH2

D Na(NH)2

Answer 1

Answer : The empirical formula of the compound is, (c)
`NaNH_2`

Solution : Given,

Moles of sodium, Na = 0.5 moles

Moles of nitrogen, N = 0.5 moles

Moles of hydrogen, H = 1.0 moles

Divide the each moles value by the smallest number of moles of given element.

`\text{ Moles of Na}=(0.5moles)/(0.5moles)=1`

`\text{ Moles of N}=(0.5moles)/(0.5moles)=1`

`\text{ Moles of H}=(1moles)/(0.5moles)=2`

The mole ratio of the elements are,

Na : N : H = 1 : 1 : 2

The mole ratio of the element is represented by the subscripts in the empirical formula.

The empirical formula is written as,
`Na_1N_1H_2` or
`NaNH_2`

Therefore, the empirical formula of the compound is, (c)
`NaNH_2`