Download App

Surface Chemistry — Chemistry STD 12 — Question

Tamilnadu BoardEnglish MediumSTD 12ChemistrySurface Chemistry3 Marks
Question
  1. Adsorption of a gas on the surface of solid is generally accompanied by a decrease in entropy. Still ¡t is a spontaneous process. Explain.
  2. How does an increase in temperature affect both physical as well as chemical adsorption?
✓

Answer

1. According to the equation ∆G = ∆H – T∆S For a process to be spontaneous, ∆G should be negative. ∆H of adsorption is always negative. For a gas. ∆S is also negative. Thus, in an adsorption process, which is spontaneous, a. combination of these two factors always makes ∆G negative.
2. On increasing the temperature desorption occurs in case of physical adsorption. Chemical adsorption first increases and then decreases with increase in temperature.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "[ 3 Marks Questions ]" from Surface Chemistry→Surface Chemistry — all question types→Chemistry STD 12 question papers→Tamilnadu Board STD 12 question papers→Tamilnadu Board question paper generator→

Similar questions

Give the uses of zinc.
→
What is Orlon? Give its preparation and use.
→
What happen when diborane heated at various temperature?
→
What happens when $XeF _6$ reacts 2.5 M solution of NaOH ?
→
Give one example for each of the following with their structure and IUPAC name.
  1. 1° alcohol
  2. 2° alcohol
  3. 3° alcohol
→
  1. What is the difference between a colloidal solution and an emulsion? Give one example of each.
  2. What are emulsifiers?
→
The decomposition of $Cl _2 O 7$ at 500 K in the gas phase to $Cl _2$ and $O _2$ is a first order reaction. After 1 minute at 500 K , the pressure of $Cl _2 O _7$ falls from 0.08 to 0.04 atm . Calculate the rate constant in s ${ }^{-1}$.
→
Sucrose and maltose are disaccharides but sucrose Is a non reducing sugar while maltose Is a reducing sugar. Give reason.
→
What are the factors which influence the adsorption of a gas on a solid?
→
1. How will you prepare
  • Acetic anhydride and
  • Acetyl chloride from acetic acid?
Write the reactions involved in each case.
2. Why is the boiling point of an acid anhydride higher than the acid from which it is derived?
→