Q16.
(a)
Need to see 3 P–H bonds and one lone pair (ignore shape).
1
(b) Coordinate / dative
If not coordinate / dative then chemical error CE=0 unless blank or covalent then M1 = 0 and mark on.
1
Pair of electrons on P(H3) donated (to H+)
Do not allow a generic description of a coordinate bond.
1
(c) 109.5° / 109½ / 109° 28ߣ
Allow answers in range between 109° to 109.5°
1
(d) Difference in electronegativity between P and H is too small
Allow P not very electronegative / P not as electronegative as N, O and F / P not electronegative enough / P not one of the 3 most electronegative elements.
Do not allow phosphine is not very electronegative.
1
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