Class 12 Chemistry - Chapter Surface Chemistry NCERT Solutions | Discuss the effect of pressure and tempe
Discuss the effect of pressure and temperature on the adsorption of gases on solids.
Effect of pressure & temperature-
According to Le Chatelier’s principle, the magnitude of adsorption should increase with fall in temperature & since adsorption of a gas leads to decrease of pressure, the magnitude of adsorption increases with increase in pressure. If a equilibrium is subjected to a stress, the equilibrium shifts in such a way as to reduce the stress. Graphically, the variation of adsorption with pressure at given constant temperature is given by adsorption isotherm.
The relationship between magnitude of adsorption & pressure can be expressed mathematically by Freundlich Adsorption isotherm i.e a = Kpn where a is the amount of gas adsorbed per unit mass of adsorbent at pressure p & K & n are constant depending upon the nature of gas & adsorbent.The value of n is less than 1 & therefore a does not increase as rapidly as p.
The effect of temperature on the extent of adsorption at a given pressure of adsorbate is given by adsorption isobar.
More Questions From Class 12 Chemistry - Chapter Surface Chemistry
- Q:-
Explain what is observed
(i) When a beam of light is passed through a colloidal sol.
(ii) An electrolyte, NaCl is added to hydrated ferric oxide sol.
(iii) Electric current is passed through a colloidal sol?
- Q:-
Why is adsorption always exothermic?
- Q:-
What do you mean by activity and selectivity of catalysts?
- Q:-
What modification can you suggest in the Hardy-Schulze law?
- Q:-
Explain the following terms:
(i) Electrophoresis
(ii) Coagulation
(iii) Dialysis
(iv) Tyndall effect.
- Q:-
What is an adsorption isotherm? Describe Freundlich adsorption isotherm.
- Q:-
Explain the terms with suitable examples:
(i) Alcosol
(ii) Aerosol
(iii) Hydrosol
- Q:-
How are colloids classified on the basis of
(i) Physical states of components
(ii) Nature of dispersion medium and
(iii) Interaction between dispersed phase and dispersion medium?
- Q:-
Why does physisorption decrease with the increase of temperature
- Q:-
What are the factors which influence the adsorption of a gas on a solid?
Popular Questions of Class 12 Chemistry
- Q:-
For the reaction R → P, the concentration of a reactant changes from 0.03 M to 0.02 M in 25 minutes. Calculate the average rate of reaction using units of time both in minutes and seconds.
- Q:-
Write the formulas for the following coordination compounds:
(i) Tetraamminediaquacobalt (III) chloride
(ii) Potassium tetracyanonickelate(II)
(iii) Tris(ethane-1,2-diamine) chromium(III) chloride
(iv) Amminebromidochloridonitrito-N-platinate(II)
(v) Dichloridobis(ethane-1,2-diamine)platinum(IV) nitrate
(vi) Iron(III) hexacyanoferrate(II)
- Q:-
(i) Write structures of different isomeric amines corresponding to the molecular formula, C4H11N
(ii) Write IUPAC names of all the isomers.
(iii) What type of isomerism is exhibited by different pairs of amines?
- Q:-
Why are solids rigid?
- Q:-
Write the structures of the following compounds.
(i) α-Methoxypropionaldehyde
(ii) 3-Hydroxybutanal
(iii) 2-Hydroxycyclopentane carbaldehyde
(iv) 4-Oxopentanal
(v) Di-sec-butyl ketone
(vi) 4-Fluoroacetophenone
- Q:-
Which of the ores mentioned in Table 6.1 can be concentrated by magnetic separation method?
- Q:-
Why are pentahalides more covalent than trihalides?
- Q:-
Silver atom has completely filled d orbitals (4d10) in its ground state. How can you say that it is a transition element?
- Q:-
Glucose or sucrose are soluble in water but cyclohexane or benzene (simple six membered ring compounds) are insoluble in water. Explain.
- Q:-
Write structures of the following compounds:
(i) 2-Chloro-3-methylpentane
(ii) 1-Chloro-4-ethylcyclohexane
(iii) 4-tert. Butyl-3-iodoheptane
(iv) 1,4-Dibromobut-2-ene
(v) 1-Bromo-4-sec. butyl-2-methylbenzene
Recently Viewed Questions of Class 12 Chemistry
- Q:-
The melting points and solubility in water of amino acids are generally higher than that of the corresponding halo acids. Explain.
- Q:-
Calculate the mass of a non-volatile solute (molar mass 40 g mol-1) which should be dissolved in 114 g octane to reduce its vapour pressure to 80%.
- Q:-
Low level of noradrenaline is the cause of depression. What type of drugs are needed to cure this problem ? Name two drugs.
- Q:-
List the important sources of sulphur.
- Q:-
How will you convert?
(i) Benzene into aniline
(ii) Benzene into N, N-dimethylaniline
(iii) Cl-(CH2)4-Cl into hexan-1, 6-diamine?
- Q:-
Indicate the types of isomerism exhibited by the following complexes and draw the structures for these isomers:
(i) K[Cr(H2O)2(C2O4)2
(ii) [Co(en)3]Cl3
(iii) [Co(NH3)5(NO2)](NO3)2
(iv) [Pt(NH3)(H2O)Cl2]
- Q:-
[Cr(NH3)6]3+ is paramagnetic while [Ni(CN)4]2- is diamagnetic. Explain why?
- Q:-
Suppose a solid solution is formed between two substances, one whose particles are very large and the other whose particles are very small. What kind of solid solution is this likely to be?
- Q:-
Write structures of the following compounds:
(i) 2-Chloro-3-methylpentane
(ii) 1-Chloro-4-ethylcyclohexane
(iii) 4-tert. Butyl-3-iodoheptane
(iv) 1,4-Dibromobut-2-ene
(v) 1-Bromo-4-sec. butyl-2-methylbenzene
- Q:-
In terms of band theory, what is the difference
(i) Between a conductor and an insulator
(ii) Between a conductor and a semiconductor
- All Chapters Of Class 12 Chemistry
- All Subjects Of Class 12