Chemical Bonding and Atomic Structure MCQs for NEET — Chemistry Questions with Answers

(c) Inspite of three polar bond,the lone pair of electrons on N atom decreases the dipole moment of $N{F}_3$ than $N{H}_3$ because in NH3 , dipole moment is getting added ,where as in NF3, dipole moment is being substracted.

(d) O is more electronegative than C.

(a) Thus, excitation of 2s-electron in N is not possible.and N doesnot have vacent d sub shell.

(d) Nearer to 25%, the angle is ${109}^{°}$28' for $s{p}^3$-hybridization.

(a) $\mu =\sqrt{{{\mu }_1}^2+{{\mu }_2}^2+{\mu }_1{\mu }_2\cos \theta }$, if $\theta ={90}^{°}$ $\mu$ is maximum.

(c) $H—$bonding order:

$‐‐‐H—F>‐‐‐H—O>‐‐‐H—N$

(b) smaller is atom, more is energy needed to remove electron , i.e.  ionisation energy. Also removal of two electrons needs more energy. 

(c) NO has 15 electrons (paramagentic ) whereas $N{O}^{+}$ has 14 electrons (Diamagnetic).

(a) No doubt $N{H}_3$ and $B{F}_3$ have $s{p}^3$ (pyramidal) and $s{p}^2$ (coplanar) hybridization respectively having one lone pair of electron on N atom which is responsible for pyramidal shape of $N{H}_3$ inspite of $s{p}^3$ hybridization. However, as soon as it is coordinated to $B{F}_3$,  both attain tetrahedral geometry and acquire $s{p}^3$- hybridization.  

 (a)

(a) :Incorrect : Because electronic transfer takes place and it is chemisorbtion.

(b) :correct: Adsorbtion is always exothermic.

(c) :correct: $O_2$ will accept the electron from metal into its $\mathrm{\pi }*2\mathrm{p}$ orbital.

(d) :correct: Since the electron enters into $\mathrm{\pi }*$ orbital bond order decrease  and bond length increases.