[问答题]
1.The bonds in ammonia
e +1e2/w2 ktkrb i2mnky: y:wu (
b2.vdy b gx8)m$NH_3$) are polar covalent.
(1)Draw the Lewis structure of ammonia.
(2)Explain why the covalent bonds in ammonia are polar.
(3)State the molecular geometry of ammonia.
(4)Explain why the bond angle of ammonia differs from that of the ammonium ion, $NH^{4+}$.
2.The boiling points of ammonia and the other group 15 compounds are shown.
Explain the variation of boiling points shown in the graph, using section 8 ($Section\,9- 2025\,Syllabus$) of the data booklet.
