Re: Is ammonia, NH3, a hydride of nitrogen or a nitride of hydrogen?

There is only one answer to this question, and that is "yes". ;-)

The usual rule is that the more electronegative element comes second, so that we 
have OF2 = oxygen difluoride, but Cl2O = chlorine monoxide.

The difficulty is that electronegativity is a slightly fuzzy concept, there are 
different scales, and they do not always agree. Nitrogen and hydrogen are very 
similar in terms of electronegativity. On balance, nitrogen would probably be 
regarded as slightly more electronegative. But traditionally (and I think it is a 
matter of tradition rather than following any particular rule), ammonia has 
always been written NH3 rather than H3N, and regarded as a hydride of nitrogen 
rather than a nitride of hydrogen.