Question

13

CHEMISTRY

136. Which is correct in case of vander Waals adsorption ?

1) high temperature, low pressure 2) high temperature, high pressure

3) low temperature, low pressure 4) low temperature, high pressure

137. Fill in the blanks by putting appropriate choices. During adsorption there is ……. In enthalpy and ….

In the entropy of a system but adsorption is a spontaneous process and thus �G must be …… Rate

of physisorption ……. With increase in pressure.

1) decrease, decrease, negative, increases 2) increase, increase, positive, decrease

3) decrease, increase, negative, decreases 4) increase, decrease, positive, increases

138. Which of the following is not correct regarding the adsorption of a gas on the surface of solid ?

1) on increasing pressure, adsorption keeps on increasing.

2) enthalpy and entropy changes are negative

3) chemisorption is more specific than physisorption

4) it is a reversible reaction

139. Which of the plots is adsorption isobar for chemisorption ?

140. In Freundlich adsorption equation x/m = kp1/m, the valuer of n is

1) always greater than one 2) always smaller

3) always equal to one

4) greater than one at low temperature and smaller than one at high temperature

141. Which of the following gases present in a polluted area will be adsorbed most easily on the charcoal

gas mask ?

1) H2 2) O2 3) N2 4) SO2

142. Match the column – I with column II and mark the appropriate choice

Column – I Column – II

a) Friedel Crafts reaction 1) Silica gel

b) Humidity control 2) x/m = kp1/m

c) Gas masks 3) anhydrous aluminium chloride

d) Freundlich adsorption isotherm 4) Adsorb poisonous gas

1) a-1, b-3, c-2, d-4 2) a-2, b-3, c-1, d-4 3) a-3, b-1, c-4, d-2 4) a-4, b-1, c-3, d-2

143. What is the role of adsorption in froth floatation process used especially for concentration of sulphide

ores ?

1) shape selective catalysts 2) adsorption of pine oil on sulphide ore particles

3) adsorption of pine oil on impurities

4) production of heat in the process of exothermic reaction

144. Match the column – I with column II and mark the appropriate choice

Column – I Column – II

a) Diastase 1) proteins-peptones

b) pepsin 2) glucose – ethyl alcohol

c) ptyalin 3) starch - maltose

d) zymase 4) starch - sugar

1) a-4, b-2, c-1, d-3 2) a-2, b-1, c-4, d-3 3) a-1, b-2, c-3, d-4 4) a-3, b-1, c-4, d-2

145. Mark the incorrect combination out of the following examples of colloidal solutions.​

Answer 1

Answer:

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