Dot & Cross Diagrams (Cambridge (CIE) A Level Chemistry): Exam Questions

Draw dot-and-cross diagrams for the following molecules.

Show outer shell electrons only.

i) Hydrogen cyanide, HCN.

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ii) Carbon dioxide, CO₂.

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iii) Boron trifluoride, BF₃.

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Use your diagrams in (a) to deduce which of the three molecules is most likely to form a coordinate (dative covalent) bond. Explain your answer.

i) Draw a dot-and-cross diagram for the product of boron trifluoride and ammonia.

Show outer shell electrons only.

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ii) Explain how the coordinate (dative covalent) bond forms between the boron trifluoride and ammonia molecules.

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