A hydride of nitrogen contains 87.5 per cent by mass fo nitrogen. Determine the empirical formula of this compound.
Constituents | Symbol | %age | Atomic mass | moles of the element = %age/at. mass (relative no. of moles) | Simplest molar ratio | Simplest whole no. ratio |
Nitrogen | N | 87.5 | 14 | 87.514=6.25 | 6.256.25=1 | 1 |
Hydrogen | H | 12.5 | 1 | 12.56.25=4.34 | 12.56.25=2 | 2 |
Thus, empirical formula (NH2).
But nitrogen forms a trivalent compound so hydride of nitrogen by 87.5 by mass % is N2H4 ( dimer of NH2).