Factors Affecting Adsorption

Q. 50 mL of 1 M oxalic acid (molar mass$=126{\text{gmol}}^{-1}$) is shaken with 0.5 g of wood charcoal. The final concentration of the solution after adsorption is 0.5 M. The amount of oxalic acid (in grams) adsorbed per gram of the charcoal is:

1. 1.575
2. 3.15
3. 12.6
4. 6.3

Q.

Discuss the effect of pressure and temperature on the adsorption of gases on solids.

Q.

Identify the gas which is readily adsorbed by activated charcoal?

1. ${\mathrm{N}}_2$

2. ${\mathrm{O}}_2$

3. ${\mathrm{SO}}_2$

4. ${\mathrm{H}}_2$

Q.

Why adsorption is a spontaneous process?

Q. why reaction of tert butyl bromide with alc KOH in presence of heat follows E1 mechanism not E2

Q.

The volume of gases $N{H}_3$, $C{O}_2$ and $C{H}_4$ adsorbed by one gram of charcoal at 298 K are in

1. CO2> NH3> CH4
2. CH4> CO2> NH3
3. NH3> CH4> CO2
4. NH3 > CO2> CH4

Q.

The mass of oxalic acid crystals required to prepare $50\mathrm{mL}$ of a $0.2\mathrm{N}$ solution is:

Q. What is work done by 0.2 mole of gas at room temperature to double its volume during isobaric process ? (R= 2 cal/mol C)

Q.

What are the factors which influence the adsorption of a gas on a solid?

Q.

The volumes of gases $H_2,C{H}_4,C{O}_{2}andN{H}_3$ absorbed by 1 g of charcoal at 288 K are in the order:

1. $H_2>C{H}_4>C{O}_2>N{H}_3$

2. $C{H}_4>C{O}_2>N{H}_3>H_2$

3. $CO2>N{H}_3>H_2>C{H}_4$

4. $N{H}_3>C{O}_2>C{H}_4>H_2$

Q. 59 two solutions, (A) containing 0.1 M FeCl3(aq) and( B )containing 0.01M K4[Fe(CN)6] are separated by semipermeable membrane as shown below . If FeCl3 on reaction with K4[Fe(CN)6] producing blue colour of Fe4[Fe(CN)6] then blue colour will be noticed in 1)A 2)B 3)In both A and B 4)neither in A nor in B

Q.

Give reason why a finely divided substance is more effective as an absorbent?

Q.

Which gas is strongly adsorbed by charcoal -

1. NH3
2. H2
3. N2
4. CO

Q. Calculate the normality of 5.3%(w/v) solution of Na2CO3 ?

Q. On the basis of data given below predict which of the following gases shows least adsorption on a definite amount of charcoal?
Gas Critical temp./K
$C{O}_2$ 304
$S{O}_2$ 630
$C{H}_4$ 190
$H_2$ 33

1. CO₂
2. SO₂
3. CH₄
4. H₂

Q. what is physical absorption?

Q.

Why is adsorption an exothermic process?

Q.

The variation of amount of gas absorbed per gram of adsorbent with pressure at different temperatures is given in the adjoining fig. Which of the following is correct relation?

1. T₃ > T₂ > T₁
2. T₂ > T₁ > T₃
3. T₁ = T₂ = T₃
4. T₁ > T₂ > T₃

Q.

When the temperature is lowered and pressure is raised, the adsorption of a gas on a solid [MP PMT 1997]

1. Decreases

2. Remains unaffected

3. Increases

4. Decreases first then increases

Q.

The volumes of gases $H_2,C{H}_4,C{O}_{2}andN{H}_3$ absorbed by 1 g of charcoal at 288 K are in the order:

1. CH₄ > CO₂ > NH₃ > H₂
2. CO₂ > NH₃ > H₂ > CH₄
3. NH₃ > CO₂ > CH₄ > H₂
4. H₂ > CH₄ > CO₂ > NH₃

Q. Adsorption isotherm

Q. What is the difference between physisorption and chemisorption?

Q. Hydrogen gas is highly flammable.

1. True
2. False

Q. During adsorption, there is a decrease in surface energy which appears as heat.

1. True
2. False

Q. write the reaction of anisole with ch3cl in presence of alcl

Q. On the basis of data given below predict which of the

Gas	$C{O}_2$	$S{O}_2$	$C{H}_4$	$H_2$
Critical temp./K	304	630	190	33

following gases shows least adsorption on a definite amount of charcoal?

1. $C{O}_2$
2. $S{O}_2$
3. $H_2$
4. $C{H}_4$

Q. For adsorption of gas on solid surface, the plots of log $x/mvs$ log $P$ is linear with a slope equal to:

1. $\text{log}c$
2. $\text{log}k$
3. $k$
4. $\frac{1}{n}$

Q. 3o2_____>2o3 is formed and enthalpy change is 286kj Find enthalpy change in formation of o3

Q.

Which reaction gives colloidal solution

1. $2HN{O}_3+3H_{2}S\to 3S+4H_{2}O+2NO$

2. $Cu+CuC{l}_2\to C{u}_{2}C{l}_2$

3. $Cu+HgC{l}_2\to CuC{l}_2+Hg$

4. $2Mg+C{O}_2\to 2MgO+C$

Q. Langmuir isotherm is a special case of Freundlich adsorption isotherms.