A nucleoside has no natural group and is not a part of a nucleic acid.
X is the gas and Y is the liquid. Intermolecular distances are farther apart in gases than in liquids.
It's the actual structure of diamond which made the two different. Diamonds have a tetrahedral structure, and as for graphite, it's not structured in that way. The structures of the two is also the reason why diamond is harder than graphite.
OK in the case of hydrazine 14 grams of nitrogen combine with 2 gram of hydrogen and with ammonia 14 grams combine with 3 grams of hydrogen.
Ratio 2:3