# Why H3P(g) called hydrogen phosphide and not hydrogen monophosphide?

$P {H}_{3}$ is $\text{phosphine gas}$...........
The boiling point of phosphine is $- 87.7$ ""^@C. The boiling point of ammonia is $- 33.4$ ""^@C. Can you explain this difference in volatility on the basis of $\text{hydrogen-bonding}$?