Question

Which of the following statements is/are true?
(i) $PH _{5}$ and $BiCl _{5}$ do not exist
(ii) $p \pi-d \pi$ bond is present in $SO _{2}$
(iii) $I_{3}^{+}$has bent geometry
(iv) $SeF _{4}$ and $CH _{4}$ have same shape

• A. (i), (ii), (iii)
• B. (i), (iii)
• C. (i), (iii), (iv)
• D. (i), (ii), (iv)

Answer 1

Answer: (A)

(i) $PH _{5}$ does not exist because the electrone gativity of $H \& P$ are almost same they should have $s p^{3} d$ hybridised but the $H$ cannot distort the $d$ orbital of $P$ hence it is not exist while $BiCl _{5} Bi ^{+3}$ is more stable than $Bi ^{+3}$ due to inert inert pair effect and in $BiCl _{5}$ steric crowding also present so it does not exist.
(ii) $S=1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{4} 3 d^{0}$
In exicited state

$p \& d$ orbital of sulphur & $p$ orbital of oxygen involved in $\pi$ bond so $S O_{2}$ has $p \pi-d \pi$ bond

(iii) $I _{3}^{+}$
$2 b p+2 l p=s p^{3}$ hybridisation
(iv) $SeF _{4} \& CH _{4}$