Q13.
(a) (i) Hydrogen bonds / H bonds
Not just hydrogen.
1
(ii)
M1 – lone pair on each N.
M2 – correct partial charges must be shown on the N and H of a bond in each molecule.
M3 – for the H bond from lone pair on N to the Hδ+ on the other NH3 molecule.
If not ammonia molecules, CE = 0 / 3.
3
(b) Lone pair / both electrons / 2 electrons / electron pair on N(H3) is donated to B(Cl3)
Allow both electrons in the bond come from N(H3).
1
(c) (i) The power of an atom or nucleus to withdraw or attract electrons or electron density or a pair of electrons (towards itself)
1
in a covalent bond
1
(ii) LiF OR Li2O OR LiH
Allow Li2O2, allow correct lithium carbide formula.
1
(iii) BH3 / H3B
Allow B2H6 / H6B2
Do not allow lower case letters.
1
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