Learn Surface Chemistry MCQ questions & answers in Physical Chemistry are available for students perparing for IIT-JEE, NEET, Engineering and Medical Enternace exam.
201.
Which of the following will show Tyndall effect?
A
Aqueous solution of soap below critical micelle concentration
B
Aqueous solution of soap above critical micelle concentration
C
Aqueous solution of sodium chloride
D
Aqueous solution of sugar
Answer :
Aqueous solution of soap above critical micelle concentration
Aqueous solution of soap above critical micelle concentration forms colloidal solution which shows Tyndall effect.
202.
At the equilibrium position in the process of adsorption ______________.
A
$$\Delta H > 0$$
B
$$\Delta H = T\Delta S$$
C
$$\Delta H > T\Delta S$$
D
$$\Delta H < T\Delta S$$
Answer :
$$\Delta H = T\Delta S$$
$$\eqalign{
& {\text{At equilibrium}},\,\Delta G = 0 \cr
& \Delta G = \Delta H - T\Delta S \cr
& \therefore \Delta H = T\Delta S \cr} $$
203.
3.6 gram of oxygen is adsorbed on $$1.2\,g$$ of metal powder. What volume of oxygen adsorbed per gram of the adsorbent at $$1\,atm$$ and $$273\,K?$$
A
$$0.19\,L{g^{ - 1}}$$
B
$$1\,L{g^{ - 1}}$$
C
$$2.1\,L\,{g^{ - 1}}$$
D
$${\text{None of these}}$$
Answer :
$$2.1\,L\,{g^{ - 1}}$$
Mass of $${O_2}$$ per gram of adsorbent $$ = \frac{{3.6}}{{1.2}} = 3$$
No. of moles of $${O_2}$$ per gram of adsorbent $$ = \frac{3}{{32}}$$
Volume of $${O_2}$$ per gram of adsorbent $$ = \frac{3}{{32}} \times \frac{{0.0821 \times 273}}{1} = 2.10$$
204.
Coagulation value of the electrolytes $$AlC{l_3}$$ and $$NaCl$$ for $$A{s_2}{S_3}$$ sol are 0.093 and 52 respectively. How many times $$AlC{l_3}$$ has greater coagulating power than $$NaCl ?$$
A
930
B
520
C
560
D
None of these
Answer :
560
$$\eqalign{
& \frac{{{\text{Coagulation power of}}\,AlC{l_3}}}{{{\text{Coagulation power of}}\,NaCl}} \cr
& = \frac{{{\text{Coagulation value of}}\,NaCl}}{{{\text{Coagulation value of}}\,AlC{l_3}}} \cr
& = \frac{{52}}{{0.093}} = 559.13 \approx 560 \cr} $$