Question

Match the following:

Column (I)	Column (II)
(A) $CH_4$ S P	(P) Have $2p_{\pi}-2p_{\pi}$ bond(s)
(B) $CS_2$ S T, Q	(Q) Have $2p_{\pi}-3p_{\pi}$ bond(s)
(C) $Cl_2$ S T, R	(R) No $\pi$ bond
(D) $S_8$ S (R,C), T(C)	(S) Molecule have $\sigma$ bond(s)
	(T) Under line atom have lone pair

• A. Have $2p_{\pi}-2p_{\pi}$ bond(s)
• B. Have $2p_{\pi}-3p_{\pi}$ bond(s)
• C. No $\pi$ bond
• D. Molecule have $\sigma$ bond(s)
• E. Under line atom have lone pair

Answer 1

A-R,S; B-Q,S,T; C-R,S,T; D-R,S,T

Answer 2

To match the compounds in Column (I) with their properties in Column (II), we analyze each compound's structure, bonding, and lone pairs.

A) $CH_4$ (Methane)

• Structure: Tetrahedral, with carbon as the central atom bonded to four hydrogen atoms.
• Bonds: All four C-H bonds are single ($\sigma$) bonds. There are no $\pi$ bonds.
• Lone Pairs: Carbon has no lone pairs. Hydrogen atoms have no lone pairs.
• Matching:
  • (P) Have $2p_{\pi}-2p_{\pi}$ bond(s): No $\pi$ bonds. (Incorrect)
  • (Q) Have $2p_{\pi}-3p_{\pi}$ bond(s): No $\pi$ bonds. (Incorrect)
  • (R) No $\pi$ bond: Correct, all bonds are $\sigma$ bonds.
  • (S) Molecule have $\sigma$ bond(s): Correct, it has four C-H $\sigma$ bonds.
  • (T) Underlined atom have lone pair: No atom in $CH_4$ has lone pairs. (Incorrect)
• Matches for A: (R), (S)

B) $CS_2$ (Carbon Disulfide)

• Structure: Linear molecule, S=C=S. Carbon is sp hybridized.
• Bonds: It has two C=S double bonds. Each double bond consists of one $\sigma$ bond and one $\pi$ bond. So, there are two $\sigma$ bonds and two $\pi$ bonds.
• $\pi$ bonds character: Carbon is a 2nd period element (uses 2p orbitals for $\pi$ bonding). Sulfur is a 3rd period element (uses 3p orbitals for $\pi$ bonding). Therefore, the $\pi$ bonds are $2p_{\pi}-3p_{\pi}$ type.
• Lone Pairs: Carbon has no lone pairs. Each sulfur atom has two lone pairs.
• Matching:
  • (P) Have $2p_{\pi}-2p_{\pi}$ bond(s): No, involves 3p of Sulfur. (Incorrect)
  • (Q) Have $2p_{\pi}-3p_{\pi}$ bond(s): Correct, C(2p)-S(3p) $\pi$ bonds are present.
  • (R) No $\pi$ bond: Incorrect, it has $\pi$ bonds.
  • (S) Molecule have $\sigma$ bond(s): Correct, it has two C-S $\sigma$ bonds.
  • (T) Underlined atom have lone pair: Correct, sulfur atoms have lone pairs.
• Matches for B: (Q), (S), (T)

C) $Cl_2$ (Chlorine molecule)

• Structure: Linear diatomic molecule, Cl-Cl.
• Bonds: It has one Cl-Cl single bond, which is a $\sigma$ bond. There are no $\pi$ bonds.
• Lone Pairs: Each chlorine atom has three lone pairs.
• Matching:
  • (P) Have $2p_{\pi}-2p_{\pi}$ bond(s): No $\pi$ bonds. (Incorrect)
  • (Q) Have $2p_{\pi}-3p_{\pi}$ bond(s): No $\pi$ bonds. (Incorrect)
  • (R) No $\pi$ bond: Correct, only a $\sigma$ bond is present.
  • (S) Molecule have $\sigma$ bond(s): Correct, it has one Cl-Cl $\sigma$ bond.
  • (T) Underlined atom have lone pair: Correct, chlorine atoms have lone pairs.
• Matches for C: (R), (S), (T)

D) $S_8$ (Cyclo-octasulfur)

• Structure: Crown-shaped puckered ring of eight sulfur atoms. All S-S bonds are single bonds.
• Bonds: It has eight S-S single bonds, all of which are $\sigma$ bonds. There are no $\pi$ bonds.
• Lone Pairs: Each sulfur atom in $S_8$ has two lone pairs.
• Matching:
  • (P) Have $2p_{\pi}-2p_{\pi}$ bond(s): No $\pi$ bonds. (Incorrect)
  • (Q) Have $2p_{\pi}-3p_{\pi}$ bond(s): No $\pi$ bonds. (Incorrect)
  • (R) No $\pi$ bond: Correct, all bonds are $\sigma$ bonds.
  • (S) Molecule have $\sigma$ bond(s): Correct, it has eight S-S $\sigma$ bonds.
  • (T) Underlined atom have lone pair: Correct, sulfur atoms have lone pairs.
• Matches for D: (R), (S), (T)

Final Matchings:

• (A) $CH_4$ $\to$ (R), (S)
• (B) $CS_2$ $\to$ (Q), (S), (T)
• (C) $Cl_2$ $\to$ (R), (S), (T)
• (D) $S_8$ $\to$ (R), (S), (T)

The final answer is $\boxed{A-R,S; B-Q,S,T; C-R,S,T; D-R,S,T}$

Explanation:

• $CH_4$: Methane has only single C-H bonds, which are $\sigma$ bonds. It contains no $\pi$ bonds and no lone pairs on any atom.
• $CS_2$: Carbon disulfide has a linear S=C=S structure. It contains two C-S $\sigma$ bonds and two C-S $\pi$ bonds. Since Carbon is a 2nd period element and Sulfur is a 3rd period element, the $\pi$ bonds are formed by $2p_{\pi}-3p_{\pi}$ overlap. Each sulfur atom has two lone pairs.
• $Cl_2$: Chlorine molecule has a single Cl-Cl bond, which is a $\sigma$ bond. It contains no $\pi$ bonds. Each chlorine atom has three lone pairs.
• $S_8$: Cyclo-octasulfur has a crown-shaped ring structure with eight S-S single bonds, all of which are $\sigma$ bonds. It contains no $\pi$ bonds. Each sulfur atom has two lone pairs.