JEE Main · 2025 · 23 Jan 2025 · Shift 1 · Chemical Bonding and Molecular Structure

Match the LIST-I with LIST-II

Answer: A → IV, B → II, C → I, D → III

Solution

Classifying each pair by the bonding at the central atom:

CC l_{4}

and

C O_{2}

each place 8 electrons around the central atom — normal octet.

BC l_{3}

and

AlC l_{3}

have only 6 electrons around

B

Al

— incomplete octet.

NO

(11 valence electrons) and

N O_{2}

(17 valence electrons) each have an odd total electron count, so one atom necessarily carries an unpaired electron with an incomplete octet.

H_{2} S O_{4}

and

PC l_{5}

place more than 8 electrons around

S

P

with d-orbital participation — expanded octet.

The correct pairing is: molecules obeying the octet rule –

CC l_{4}, C O_{2}

; incomplete octet –

BC l_{3}, AlC l_{3}

; incomplete octet with odd electron –

NO, N O_{2}

; expanded octet –

H_{2} S O_{4}, PC l_{5}

JEE Main · 2025 · 23 Jan 2025 · Shift 1 · Match the columns