Chemisorption

Q. If $x$ is amount of adsorbate and $m$ is amount of adsorbent, which of the following relations is not related to adsorption process ?

1. $\frac{x}{m}=p\times T$
2. $x/m=f\left(T\right)$ at constant $p$
3. 
   $x/m=f\left(p\right)$ at constant $T$
4. $p=f\left(T\right)$ at constant $x/m$

Q.

The correct statement(s) pertaining to the adsorption of a gas on a solid surface is (are)

1. Adsorption is always exothermic.

2. Physisorption may transformation into chemisorption at high temperature.

3. Physisorption increases with increasing temperature but chemisorption decreases with increasing temperature.

4. Chemisorption is more exothermic than physisorption; however, it is very slow due to higher energy of activation.

Q.

Does adsorption increase with temperature?

Q.

Easily liquefiable gases have

1. Low Boyle temperature

2. High Boyle temperature

3. Both the above

4. None of the above

Q. Graph between $\log \left(\frac{x}{m}\right)$ and $\log P$ is a straight line at an angle ${45}^{\circ }$ with intercept on $y$-axis $0.3010$. The amount (in $g$) of the gas absorbed per $g$ of the adsorbent when pressure is $0.2atm$ is:
(Assume that the adsorption obey Freundlich isotherm)

1. $0.4$
2. $0.6$
3. $0.8$
4. $0.2$

Q. Calculate vont hoff factor for Fe(NH4)2(SO4)2

Q.

How does physisorption change to chemisorption at high temperatures?

Q.

What role does adsorption play in heterogeneous catalysis ?

Q. Packing fraction of face centered cibic unit cell

Q.

Is chemisorption reversible or irreversible?

Q. Vomule of gases H2, CH4 , CO2 & NH3 adsorbed by 1g of charcoal at 288K are in the order ? Explain why ?

Q.

The rate of chemisorption :

1. increases with increase of pressure
2. is independent of pressure
3. is independent of temperature
4. decreases with increase of pressure

Q. density of KBr is 2.75g/cm3 . the edge length of unit cell is 654pm . find the type of unit cell of KBr .

Q. Which of the following is correct for chemical adsorption?

1. Increases with an increase in temperature
2. Decreases with an increase in temperature
3. First increases, then decreases with an increase in temperature
4. First decreases, then increases with an increase in temperature

Q.

Chemisorption

1. Remains unaffected by change of temperature

2. Either increases or decreases with temperature

3. Increases with temperature

4. Decreases with temperature

Q.

It's easier to liquify oxygen than hydrogen because:
a) oxygen has a higher critical temperature and lower inversion temperature than hydrogen
b) oxygen has a lower critical temperature and higher inversion temperature than hydrogen
c) oxygen has a higher critical temperature and higher inversion temperature than hydrogen
d) the critical temperature and inversion temperature of oxygen is very low

Q. 54. How many faradays are needed for reduction of 2.5 mole Cr, 0? into Cr+3? (1) 15 (3) 6 (2) 12 (4) 3

Q.

Chemisorption said to be irreversible but the graph between temperature and chemisorption decrease after the activation energy indicating desorption? Why?

Q. Write any four differences between physisorption and chemisorption.

Q. Which one of the following is not a property of physical adsorption?

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> JEE Mains 2018

Q. for a reaction, activation energy Ea= 0 and the rate constant at 200 K is 1.6 x 10^6 s^-1. the rate constant at 400 K will be [Given that gas constant, R= 8.314 J K^-1 mol^-1]

Q. Which of the following is not characteristic of chemisorption?

1. Adsorption is specific
2. Heat of adsorption is of die order of $200kJmo{l}^{-1}$
3. Adsorption may form multimolecular layers
4. Adsorption is irreversible

Q.

Enthalpy of chemisorption is in the order of?

1. 20 - 40 kJ per mol

2. 80 - 240 kJ per mol

3. 30 - 1000 kJ per mol

4. 40 - 80 kJ per mol

Q.

Chemisorption

1. Increases with temperature

2. Decreases with temperature

3. Remains unaffected by change of temperature

4. Either increases or decreases with temperature

Q. Select the correct statement(s).
1. Adsorption is spontaneous at all the temperatures.
2. Gases having high critical temperature possess more tendency for adsorption.
3. An adsorbent possesses more tendency for adsorption if it is in colloidal state.
4. Chemical adsorption first decreases with increase in temperature and then increases.
5. Water molecules are adsorbed in $CaC{l}_2\left(s\right)$ results in increasing temperature.

1. $1,2,3,4,5$
2. $2,3,4$
3. $1,2,3,4$
4. $2,3$

Q. Write any two characteristics of chemisorption.

Q. On the basis of Langmuir adsorption isotherm, the amount of gas adsorbed at very high pressure:

1. reaches a constant limiting value
2. goes on increasing with pressure
3. goes on decreasing with pressure
4. first increasing and then decreasing with pressure

Q. Answer in one word:
Out of physisorption and chemisorption which on has lower enthalpy of adsorption?

Q. The gas with lower critical temperature is easily adsorbed on platinum
If true then enter 1 else enter 0.

Q.

FeCl₃ on reaction with potassium ferrocyanide in aqueous solution gives blue colour.When 0.01M of FeCl₃ and 0.1M potassium ferrocyanide are placed in a beaker and seperated by a semi permeable membrane, identify whether there will be an appearance of blue colour on potassium ferrocyanide side due to osmosis.E xplain your answer.