This question is about structure and chemical bonding.
Look at the two structures, A and B, in Fig. 21.1.

Fig. 21.1
Identify the bonding in structure A. Explain your answer.
Bonding: …………………………………………………………………………………………\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots…………………………………………………………………………………………
Explanation: …………………………………………………………………………………………\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots…………………………………………………………………………………………
Explain why structure B has a high melting point.
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Explain why structure B does not conduct electricity when solid.
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Look at the structure of hexagonal boron nitride (h-BNh\text{-BN}h-BN) in Fig. 21.2. Hexagonal boron nitride has a slippery feel and is widely used as a high-temperature lubricant.

Fig. 21.2
Explain why hexagonal boron nitride is slippery.
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