Adsorption

Question 1

adsorption

Answer 1

adsorption is a surface proces that leads to transfer of a molecule from fluid bulk to a olid surface. This can occur because physical forces or by chemical bondes
or
adsroption is the adhesion, of atoms ions, or molecules froma gas liquid, or dissolved solid to a surface
ex) painting on walls, water droplets on window

Question 2

adsorbate

Answer 2

subtances which is deposited on the surface of another substance
Ex) H2, N2, O2

Question 3

adsrobent

Answer 3

surface of the substace on which adorbent adsorbs
ex) charcoal, silica gel, alumina

Question 4

physical adsorption

Answer 4

also known as physisorption. it is due to weak van der waal forces betweena adrobate and adsrobent.
Ex) H2, or N2, adsorbs on charcoal

Question 5

chemical adsorption

Answer 5

also known as chemimisorption. it is due to strong chemical forces of bonding type between adsorbate and adsrobent. we can take the example involving the formation iron nitride on the surface when iron is heated. adsorption on gas on a solid is a spontaneous exothermic reaction

Question 6

characteristics of physical adsorption

Answer 6

-surface area, temp, pressue, nature of adsorbate affects PA
-energy for activation is low (20-40Kj/mole)
-this type of adsorption is caused by physical forces
-physisorption is a weak phenomenon
-this type of adsorption is almost a multi-layered phernomenon
-it is reversible

Question 7

characterstics of chemical adsorption

Answer 7

-surface area, temperaure, nature of adorbate effect chemisorption
-energy of activation is very high 40-400KJ/mole
-it is very strong process
-thi type of adsorption is almost a single layered phenomenon
-it is irreversible

Question 8

factors affecting extent of adsorption

Answer 8

-nature of adsorbent
-surface area
-nature of gase
-exothermic nature
-pressue

Question 9

nature of adsorbent

Answer 9

the adsorption of the gas depends on the nature of the adsorbent. A gas can be adsorbed on different adsorbent surfaces in different amounts

Question 10

surface area

Answer 10

when we increase the surface area of the adsobent there is an increase in the adsrption of gases. This is because when we increase the surface area there is more number of adsorbing sites. so finely divided solid and some porous substances are good substances

Question 11

nature of the gas

Answer 11

in general, it a gas is more liquifiable it will be more easily adsorbed. For examples gases like NH3, HCL, Cl2, CO2, which can be liquified easily are more readily adsorbed on the solids surface rather than permanent gases like O2, H2, etc.

Question 12

exothermic nature

Answer 12

the heat of adsorption can be defined as the energy liberated when 1g mole of gas is adsorbed on a solid surace. Doing the process of adsorption adsorbent surface forms bonds with adsorbate molecules which increases stability abd releases energy

Question 13

pressure

Answer 13

on the solid surface, there is a fixed number of adsorption sites where gas molecules can be adsorbed. Initially when the pressure has increases the rate of adsorption increases due to increase in the gas molecules striking on the surface, Thus an increase in the pressure increases the rate of adsorption linearly

Question 14

applications of adsorption

Answer 14

-air pollution masks
-purification of water/softening hard ward
-removal of moisture and humidity
-in preserving vacuum
-in paint industry
-in dyeing
-recovery of chemical from industrial gases

Question 15

application of adsorption in pharmacy

Answer 15

adsorption of small drug particles on the surface of large excipients has been widely used in the pharmaceutical industry for various purposues, such as improving content uniformly of low-dose drugs, enhancing the dissolution rate for poorly water-soluble drug. used in chromotography technuques for the separation of organic substances