JEE Advanced levelSingle correct optionDifficulty 3 of 3pb161
Assertion (A): SiOX2 is a high-melting solid whereas COX2 is a gas. Reason (R): Silicon forms strong pπ-pπ double bonds with oxygen, just as carbon does.
ABoth A and R are true and R is the correct explanation of A
BBoth A and R are true but R is not the correct explanation of A
CA is true but R is false
DA is false but R is true
Answer: C
A is true: SiOX2 is a giant covalent network of Si-O single bonds, whereas COX2 is a discrete O=C=O molecule. R is false: Si, being larger, forms poor pπ-pπ overlap, so it prefers four Si-O single bonds.