Which of the following set is having correct statements?
$1 .$ Molecular crystals are hard in nature
$2 .$ Silicon carbide is a covalent crystal
$3 .$ Increase in radius ratio results in increase in coordination number
$4 .$ In calcium fluoride structure, coordination number of $C a^{2 +}$ is 4

Question

TestHub · Accepted Answer

Molecular crystals are soft in nature so statement 1 is incorrect.
As coordination number of $C a^{2 +}$ in $C a F_{2}$ is 8 and that of $F^{-}$ is 4 so statement 4 is incorrect.
Here statement 2 and 3 are correct.
Silicon carbide (SiC) is a covalent crystaline solid.
Coordination number $\propto$ radius ratio.
Hint : Molecular crystals are soft.

Chemistry - Solid State Question with Solution | TestHub

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