(a) Based on the nature of intermolecular forces, classify the following solids: Silicon carbide, Argon (b) ZnO turns yellow on heating. Why? (c) What is meant by groups 12-16 compounds? Give an example.

(a) Based on the nature of intermolecular forces, classify the followi

1.	(a) Based on the nature of intermolecular forces, classify the following solids: Silicon carbide, Argon (b) ZnO turns yellow on heating. Why? (c) What is meant by groups 12-16 compounds? Give an example.
Answer» (a) Silicon carbide (sic)=Covalent or network Argon-Molecular (non polar) (b) When ZnO is heated, it loses oxygen `ZnOtoZn^(2+)+(1)/(2)O_(2)+2e^(-)` `Zn^(2+)` ions are entrapped in the interstitial voids and `e^(-)` s in the neighbouring interstitial voids to maintain electrical neutrality. this gives rise to metal excess defect. due to the presence of `e^(-)`s in voids, the colour is yellow. (c) Semiconductors which are prepared by combination of elements of group 12 and group.

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(a) Based on the nature of intermolecular forces, classify the following solids: Silicon carbide, Argon (b) ZnO turns yellow on heating. Why? (c) What is meant by groups 12-16 compounds? Give an example.

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