A. $\rightarrow(5)$

B. $\rightarrow$ (1)

C. $\rightarrow(2)$

$\mathrm{D} \rightarrow(3)$

A. $\mathrm{H}_3 \mathrm{O}^{+}=3 b p+1 / p$ pyramidal shape

B. $\mathrm{HC} \equiv \mathrm{CH} \Rightarrow$ linear as sphybridised shape

C. $\mathrm{ClO}_2^{-}=2 b p+2 / p \Rightarrow$ angular shape

D. $\mathrm{NH}_4^{+}=4 b p+0 / p \Rightarrow$ tetrahedral shape

A. $\rightarrow$ (3)

B. $\rightarrow$ (4)

C. $\rightarrow(1)$

D. $\rightarrow(2)$

$$ \begin{gathered} \text { A. } N O(7+8=15)=\sigma 1 s^2, \sigma^{\star} 1 s^2, \sigma 2 s^2, \sigma^{\star} 2 s^2, \sigma 2 p_z^2, \pi 2 p_x^2 \approx \pi 2 p_y^2, \pi \star 2 p_x^1 \\ \text { Bond order }=\frac{1}{2}\left(N_b-N_a\right)=\frac{10-5}{2}=2.5 \end{gathered}$$

B. $\mathrm{CO}(6+8=14)=\sigma 1 s^2, \sigma^{\star} 1 s^2, \sigma 2 s^2, \sigma^{\star} 2 s^2, \sigma 2 p_z^2, \pi 2 p_x^2 \approx \pi 2 p_y^2$

Bond order $=\frac{10-4}{2}=3$

C. $\mathrm{O}_2^{-}(8+8+1=17)=\sigma 1 s^2, \sigma^{\star} 1 s^2, \sigma 2 s^2, \sigma * 2 s^2, \sigma 2 p_z^2, \pi 2 p_x^2 \approx \pi 2 p_y^2, \pi * 2 p_x^2 \approx \pi * 2 p_y^1$

Bond order $=\frac{10-7}{2}=1.5$

D. $\mathrm{O}_2(8+8=16)=\sigma 1 s^2, \sigma^{\star} 1 s^2, \sigma 2 s^2, \sigma^{\star} 2 s^2, \sigma 2 p_z^2, \pi 2 p_x^2 \approx \pi 2 p_y^2, \pi^{\star} 2 p_x^1 \approx \pi^{\star} 2 p_y^1$

Bond order $=\frac{10-6}{2}=2$

A. $\rightarrow$ (4)

B. $\rightarrow$ (5)

C. $\rightarrow$ (2)

D. $\rightarrow$ (1)

A. Hydrogen bond $\rightarrow \mathrm{HF}$

B. Resonance $\rightarrow \mathrm{O}_3$

C. Ionic bond $\rightarrow$ LiF

D. Covalent solid $\rightarrow \mathrm{C}$

A. $\rightarrow(3)$

B. $\rightarrow(1)$

C. $\rightarrow(2)$

A. Tetrahedral shape $-s p^3$ hybridisation

B. Trigonal shape $-s p^2$ hybridisation

C. Linear shape - sp hybridisation