Chemistry NCERT Exemplar Solutions Class 11th Chapter Eleven

Teflon are prepared by addition polymerization from tetrafluroethene.
CF? = CF? - (catalyst, High pressure)-> [–CF? – CF? –]? Teflon
Nylon-66, Novolac, Dacron are prepared by condensation polymerisation.

The number of Body centred unit cells in all 14 types of Bravais lattice unit cells is 3.

(4) C? H? O will have different alkyl group attached with polyvalent functional group that's why show metamerism

Only one arrangement possible so can not show metamerism.
(2) C? H? O → CH? – O – CH? – CH? Only one arrangement possible so can not show metamerism.
(1) No polyvalent functional group in C? H? , so can not show metamerism.

At room temperature Hg is liquid and it is purified by 'Distillation method'.

BeCl? in solid state exist in a polymeric form & in a vapour state in exist in a dimeric form.

chain polymeric structure
Vapour state exist in a dimeric form

According to Boyle's law

P ∝ 1/V

At a given pressure,

V ∝ T

| H – F | H – Cl | H – Br | H – I |
| :- | :- | :- | :- |
| 1s – 2p | 1s – 3p | 1s – 4p | 1s – 5p |

Down the group size increases
Overlapping decreases
Acidic strength increases

Tyndall effect is exhibited by colloidal solutions.
Starch solution is a colloidal solution

Dimethylammonium acetate is a weak acid & weak base type of salt.
pH = 7 + ½ pK? – ½ pK?
= 7 + ½ * 4.77 – ½ * 3.27
= 7.75