Question

Which of the following statements is/are true?
1) $P{H}_5$ and $BiC{l}_5$ do not exist.
2) $p\pi -d\pi$ bond is present in $S{O}_2$.
3) $I_3^{+}$ has bent geometry.
4) $Se{F}_4$ and $C{H}_4$ have same shape.

• A. 1, 2, 3
• B. 1, 3
• C. 1 and 2
• D. 1, 2, 4

Answer 1

Answer: (A)

1, 2, 3

For $P{H}_5$ and $BiC{l}_5$, P and Bi have to extend the octet, hydrogen and chlorine don't have sufficient electronegativity to excite electrons to vacant d-orbitals in P and Bi respectively.
So, $P{H}_5$ and $BiC{l}_5$ don't exist.

In $S{O}_2$, sulphur is $s{p}^2$ hybridised and 1 lone pairs are present. Hence, the $2\pi$ bond with 2 oxygen atoms are 1 $p\pi -p\pi$ and $p\pi -d\pi$ bonds.

In $I_3^{+}$, due to 2 lone pairs of electrons and 2 bond pairs on the central atom, it has a bent shape.

$C{H}_4$ has 4 bond pair and no lone pair and is tetrahedral while $Se{F}_4$ with 4 bond pair and 1 lone pair is see-saw shape.