Question 1

Paper 2Medium4 marks

Figure 1 shows Lewis representations of ammonia, \ceNH3\ce{NH3} and methane, \ceCH4\ce{CH4} Each line represents a single covalent bond. The arrangements shown do not represent the three-dimensional molecular shapes.

NH3CH4NHHHCHHHH
(a)

State the electron-domain geometry around the central atom in each molecule.

[1]
(b)

Compare the molecular geometries of \ceNH3\ce{NH3} and \ceCH4\ce{CH4}

[1]
(c)

The H–N–H bond angle in \ceNH3\ce{NH3} is smaller than the H–C–H bond angle in \ceCH4\ce{CH4} Explain why.

[2]

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