Chemical Bonding and Molecular Structure

This option is correct. In Pb⁺² inert pair effect is there i.e. because of lanthanoid contraction , poor shieding effect of  4f¹⁴  electrons . The effective nuclear charge increases and after removal of two  electrons it becomes really hard to remove the other two electrons . Hence, Pb⁺² is most stable among its group because lanthanoids contraction observe in this atom only .

This option is correct because , in ClOH chlorine has three lone pair and the electron on O^- is unable to delocalise itself . Hence, it will remain on oxygen atom and  has the highest basicity among the given options .  

This option is correct because , during the hydrolysis ,  water being neucleophile always prefer to attack the central atom first . it will attack the central atom  only when it posses vacant orbitals . If the central atom doesn't posses vacant orbital then attack  of water molecules taken place on peripheral atom provided they also posses vacant orbitals . in this case niether central nor peripheral atom posses vacant orbital hence hydroysis doesn't takes place in this molecule . 

This option is correct. Bond order of N₂ = 3. Bond order of N₂⁺ = 2.5. Bond order of N₂^- = 2.5. Since bond order of N₂⁺ and N₂^- is the same, but the effective nuclear charge of N₂⁺ is more than that of N₂^-, so the correct order is N₂ > N₂⁺ > N₂^-.

You might have remembered  this logic  , if the total number of electrons comes out to be 50  the hybridisation is capped octahedral i.e. sp³d² or distorted octahedral .  

this option is correct because , in case of homoneuclear molecule it is easy to calculate the magnetic character through molecular orbital theory . but in case of hetronuclear molecule one  easy method is there to find out the magnetic character . magnetic character in case of hetronuclear molecules . 1. count  the total number of valence electrons if it comes out to be even then it is dimagnetic otherwise paramagnetic . in this case Cl has 7 valence electrons and oxygen has 6 valence electrons . so total number of valence electrons is 7 + 6 x 2 = 19 , which is odd hence this molecule is paramagnetic . and this option is correct  .   

XeF₂ has three lone pairs of electrons with linear geometry.

SF₄ has one lone pair of electrons with seesaw geometry.

I^3- and XeF₂ both have three lone pair of electrons with linear geometry. HgCl₂ has zero lone pair of electrons with linear geometry. SO₂ has one lone pair of electron with bent shape.  Hence, 1, 2, 3 all molecules have linear geometry.

P. NH₃ and PCl₃ both molecules have one lone pair of electrons with trigonal pyramidal geometry. S. CO₂ has zero lone pair of electrons with linear geometry. XeCl₂ has three lone pairs of electrons with linear geometry. Hence, P and S statements are incorrect.

The capped square antiprismatic molecular geometry describes the shape of compounds where nine atoms, groups of atoms, or ligands are arranged around a central atom, defining the vertices of a gyroelongated square pyramid. Example is ReH₉^2-.

According to VSEPR theory, BrF₄^- and XeF₄ both have four bond pair of electrons and two lone pair of electrons with square planar shape. TeCl₄ has four bond pair of electrons and one lone pair of electrons with distorted trigonal bipyramidal shape.  Hence, 1 and 2 have square planar shape.

The nitronium ion or sometimes the nitryl ion NO₂⁺ is a generally reactive cation created by the removal of an electron from the paramagnetic nitrogen dioxide molecule. In [O = N = O]+ nitrogen atom has sp hybridisation and thus it is linear in shape. In NO2- the nitrogen atom has sp2 hybridisation and bent shape.

P. XeCl₂ has three lone pairs of electrons with linear geometry. Q. XeF₆ has six bond pairs of electrons and one lone pair of electrons with distorted pentagonal bipyramidal shape. R. ICl₄^- ion and XeF₄ molecule has four bond pairs of electrons and two lone pair of electrons with square planar geometry. Hence, only the statement P is false.

SF₄ and XeO₂F₂ have sp³d hybridisation and one lone pair of electrons with seesaw geometry. XeOF₂ has sp³d hybridisation and two lone pairs of electrons with T-shaped geometry. XeO₃F₂ has sp³d hybridisation and zero lone pair of electrons with trigonal bipyramidal geometry.