common mistakes SQP1

Question 1

mercury cell overall reaction

Answer 1

Zn(Hg)+HgO—– ZnO+Hg

Question 2

mercury delivers a constant potential during its life time

Answer 2

it is because the overall reaction
Zn(Hg)+HgO—– ZnO+Hg
does not involve any ions therefore delivers constant life.

Question 3

in the experimental determination of electrolysis conductance,DC is not used.

Answer 3

if DC current is used it will lead to polarisation of electrolysis of electrodes and electrolysis of the sol leading to error in conductance reading. hence thats why.

Question 4

what is a chelate complex, give example

Answer 4

When a di- or polydentate ligand uses its two or more donor atoms simultaneously to bind a single metal ion, it is said to be a chelate ligand. Such complexes are called chelate complexes
eg. ethylenediamine (en)

Question 5

what are heteroleptic complexes

Answer 5

Heteroleptic complexes are those in which a metal ion is surrounded by more than one type of ligand
eg- [Co(NH3)4Cl2]+

Question 6

why ortho nitro phenol is steam volatile while para nitrophenol is not?

Answer 6

in O-nitro phenol, INTRAmolecular H- bonding is present which leads to less association and easy bond breakage in comparison to p-nitrophenol where strong INTERmolecular bond is present. therefore o-nitro phenol is steam volatile.

Question 7

Sn2 order?

Answer 7

1>2>3

Question 8

why p-nitrochlorobenzene has higher melting point than those of ortho and meta isomer?

Answer 8

it has more symmetry and better packing efficiency in comparison to o,m hence higher m.p