Chemistry NCERT Exemplar Solutions Class 12th Chapter Five

Geraniol, a volatile organic compound, is a component of rose oil. The density of the vapour is 0.46 gL^-1 at 257°C and 100 mm Hg. The molar mass of geraniol is___________ g mol^-1 (Nearest Integer).

[Given R = 0.082 L atm K^-1 mol^-1]

A 10g mixture of hydrogen and helium is contained in a vessel of capacity 0.0125 m³ at 6 bar ansd $27°$ C. The mass of helium in the mixture is__________g. (nearest integer)

Given below are two statements : one is labeled as Assertion A  and the other is labeled as Reason R.

Assertion A: Finest gold is red in colour, as the size of the particles increase, it appears purple then blue and finally gold.

Reason R: The  colour of the colloidal solution depends on the wavelength of light scattered by the dispersed particles.

In the light of the above statements, choose the most appropriate answer from the options given below.

The nature of charge on resulting colloidal particles when FeCl₃ is added to excess of hot water is

Given below are two statements : One is labeled as Assertion A and the other is labeled as Reason R

Assertion A: Thin layer chromatography is an adsorption chromatography.

Reason R: A thin layer of silica gel is spread over a glass plate of suitable size in thin layer chromatography which acts as an adsorbent.

In the light of the above statements, choose the correct answer from the options given below

Match the following:

The Zeta potential is related to which property of colloids

The minimum uncertainty in the speed of an electron in an one dimensional region of length 2a₀ (Where a₀ = Bohr radius 52.9 pm) is__________ km s^-1.

(Given: Mass of electron = 9.1 * 10^-31 kg, Planck's constant h = 6.63 * 10^-34 Js)

100 mL of 5% (w/v) solution of NaCl in water was prepared in 250 mL beaker. Albumin from the egg was poured into NaCl solution and stirred well. This resulted in a/an:

A sample of red ink (a colloidal suspension) is prepared by mixing eosine dye, egg white, $\mathrm{H}\mathrm{C}\mathrm{H}\mathrm{O}$  and water. The component which ensures stability of the ink sample is :