1
IIT-JEE 1993
Subjective
+2
-0
The standard reduction potential for the half-cell
$$NO_3^-$$ + 2H+ (aq) + e $$\to$$ NO2 (g) + H2O is 0.78 V
(i) Calculate the reduction potential in 8 M H+
(ii) What will be the reduction potential of the half-cell in a neutral solution? Assume all the other species to be at unit concentration.
2
IIT-JEE 1993
Subjective
+2
-0
Chromium metal can be plated out from an acidic solution containing CrO3 according to the following equation
CrO3 (aq) + 6H+ (aq) + 6e- $$\to$$ Cr(s) + 3H2O
Calculate (i) how many grams of chromium will be plated out by 24,000 coulombs and (ii) how long will it take to plate out 1.5 g of chromium by using 12.5 amp current.
3
IIT-JEE 1992
Subjective
+4
-0
For the galvanic cell
Ag | AgCl(s), KCl (0.2M) || KBr (0.001M), AgBr(s) | Ag
Calculate the EMF generated and assign correct polarity to each electrode for a spontaneous process after taking into account the cell reaction at 25oC.
[Ksp(AgCl) = 2.8 $$times$$ 10-10; Ksp(AgBr) = 3.3 $$times$$ 10-13]
4
IIT-JEE 1992
Subjective
+3
-0
An aqueous solution of NaCl on electrolysis gives H2(g), Cl2(g) and NaOH according to the reaction:
2Cl- (aq) + 2H2O = 2OH- (aq) + H2 (g) + Cl2 (g)
A direct current of 25 amperes with a current efficiency of 62 % is passed through 20 litres of NaCl solution (20% by weight). Write down the reactions taking place at the anode and cathode. How long will it take to produce 1kg of Cl2? What will be the molarity of the solution with respect to hydroxide ion? (Assume no loss due to evaporation)
EXAM MAP
Medical
NEET