Why does $\ce{NH2OH}$ have a lower boiling point than water? According to Wikipedia, hydroxyamine has a boiling point of 58 °C. Could this be due to the extent of hydrogen bonding among both molecules?

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    $\begingroup$ Before you ask "why", ask "if". Did you just ignore those "22 mm Hg" as meaningless? $\endgroup$ – Ivan Neretin Jun 8 '17 at 12:46
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    $\begingroup$ I don't understand why this question was downvoted. Agreed, it's quite small but I don't see what else we should expect from a asker. The question is quite genuine too. $\endgroup$ – Pritt says Reinstate Monica Jun 8 '17 at 13:52
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    $\begingroup$ @PrittBalagopal Based on Ivan's comment, the question was downvoted (not necessarily by him) because the statement it makes is incorrect. Hydroxylamine would have a higher boiling point than water at 1 atm, if it did not decompose from heating. I don't mind this so much, since it's an honest mistake, and there's something to be learned from it. $\endgroup$ – Zhe Jun 8 '17 at 14:03
  • $\begingroup$ Think about ammonia (NH$_3$) it has a bp. of -33.4°C , that tells about the possible intermolecular interactions between NH$_3$ molecules. They are much worse than those in water. In H$_2$NOH you are about in between. Very roughly speaking. It doesn't work perfectly, (averaging between H$_2$O$_2$ and hydrazine would give you a very bad estimate (actually above 100°C). That shows that the business is not that easy ... $\endgroup$ – Rudi_Birnbaum Jun 8 '17 at 17:35

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