1. Molar conductivity of $$0.15\,M$$  solution of $$KCl$$  at $$298\,K,$$  if its conductivity is $$0.0152\,S\,c{m^{ - 1}},$$   will be

A. $$124\,{\Omega ^{ - 1}}c{m^2}\,mo{l^{ - 1}}$$
B. $$204\,{\Omega ^{ - 1}}c{m^2}\,mo{l^{ - 1}}$$
C. $$101\,{\Omega ^{ - 1}}c{m^2}\,mo{l^{ - 1}}$$
D. $$300\,{\Omega ^{ - 1}}c{m^2}\,mo{l^{ - 1}}$$
Answer :   $$101\,{\Omega ^{ - 1}}c{m^2}\,mo{l^{ - 1}}$$
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2. Given
$$E_{\frac{{C{u^{2 + }}}}{{Cu}}}^ \circ = 0.34V,E_{\frac{{C{u^{2 + }}}}{{Cu}}}^ \circ = 0.15\,V$$
Standard electrode potential for the half cell $$\frac{{C{u^ + }}}{{Cu}}$$  is

A. 0.38$$\,V$$
B. 0.53$$\,V$$
C. 0.19$$\,V$$
D. 0.49$$\,V$$
Answer :   0.53$$\,V$$
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3. When electric current is passed through acidified water, $$112\,mL$$  of hydrogen gas at $$STP$$  collected at the cathode in 965 seconds. The current passed in amperes is

A. 1.0
B. 0.5
C. 0.1
D. 2.0
Answer :   1.0
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4. Aqueous solution of which of the following compounds is the best conductor of electric current?

A. Acetic acid, $${C_2}{H_4}{O_2}$$
B. Hydrochloric acid, $$HCl$$
C. Ammonia, $$N{H_3}$$
D. Fructose, $${C_6}{H_{12}}{O_6}$$
Answer :   Hydrochloric acid, $$HCl$$
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5. The equivalent conductance at infinite dilution of a weak acid such as $$HF$$

A. can be determined by extrapolation of measurements of dilute solutions of $$HCl, HBr$$   and $$HI$$
B. can be determined by measurement of very dilute $$HF$$  solutions
C. can be determined from measurements of dilute solutions of $$NaF, NaCl$$   and $$HCl$$
D. is an undefined quantity
Answer :   can be determined from measurements of dilute solutions of $$NaF, NaCl$$   and $$HCl$$
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6. The limiting equivalent conductivity of $$NaCl,KCl$$   and $$KBr$$  are $$126.5,150.0$$   and $$151.5\,S\,c{m^2}\,e{q^{ - 1}},$$    respectively. The limiting equivalent ionic conductivity for $$B{r^ - }$$  is $$78\,S\,c{m^2}e{q^{ - 1}}.$$   The limiting equivalent ionic conductivity for $$N{a^ + }\,ions$$   would be :

A. 128
B. 125
C. 49
D. 50
Answer :   50
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7. In electrolysis of $$NaCl$$  when $$Pt$$  electrode is taken then $${H_2}$$  is liberated at cathode while with $$Hg$$  cathode it forms sodium amalgam because

A. $$Hg$$  is more inert than $$Pt$$
B. more voltage is required to reduce $${H^ + }$$ at $$Hg$$  than at $$Pt$$
C. $$Na$$  is dissolved in $$Hg$$  while it does not dissolved in $$Pt$$
D. concentration of $${H^ + }$$ $$ions$$  is larger when $$Pt$$  electrode is taken
Answer :   more voltage is required to reduce $${H^ + }$$ at $$Hg$$  than at $$Pt$$
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8. Standard electrode potential of three metals $$X, Y$$  and $$Z$$ are $$-1.2$$ $$V,$$ $$+ 0.5$$ $$V$$ and $$-3.0$$ $$V$$ respectively. The reducing power of these metals will be

A. $$Y > X > Z$$
B. $$Z > X > Y$$
C. $$X > Y > Z$$
D. $$Y > Z > X$$
Answer :   $$Z > X > Y$$
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9. Zinc can be coated on iron to produce galvanised iron but the reverse is not possible. It is because

A. zinc is lighter than iron
B. zinc has lower melting point than iron
C. zinc has lower negative electrode potential than iron
D. zinc has higher negative electrode potential than iron
Answer :   zinc has higher negative electrode potential than iron
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10. On the basis of the information available from the reaction. $$\frac{4}{3}Al + {O_2} \to \frac{2}{3}A{l_2}{O_3},$$     $$\Delta G = - 827kJ\,mo{l^{ - 1}}$$     of $${O_2},$$  the minimum $$EMF$$  required to carry out the electrolysis of $$A{l_2}{O_3}$$  is $$\left( {F = 96500\,C\,mo{l^{ - 1}}} \right)$$

A. 2.14$$\,V$$
B. 4.28$$\,V$$
C. 6.42$$\,V$$
D. 8.56$$\,V$$
Answer :   2.14$$\,V$$
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