Last seen: Oct 19, 2020
(b) The standard EMF of the cell is -0.27 V. Explanation: E°cell = E°cathode - E°anode = E°right - E°left E°cell = 0.25 - 0.52 = -0.27 V
(c) decrease by 0.41 V Explanation: pH changes from 0 to 7. ∴ [H+] changes from 1 to 10-7M Accordingly Ered. = -0.059/n log 1/[H+] = 0.059 l...
(b) A, B, C Explanation: The more the reduction potential, the more is the deposition of metals at cathode. Cation having E° value less than -0.83...
(a) Zn (s) Explanation: Since oxidation potential of Zn is highest hence strongest reducing agent.
(c) 0.015 Explanation: k = 1/R x Cell constant = 0.47/31.6 = 0.01487
(d) Fe(s) Explanation: K+ (aq) and Zn2+ (aq) can not lose electron(s). Fe has greater tendency to lose electrons than Cu. [E°Fe2+/Fe = -0.44V &g...
(d) (x1 + x2 – 2x3) /2 Explanation: 2s.png
(b) 23.2 S cm2 mole-1 Explanation: Here, R = 31.6 ohm ∴ C = 1/R = 1/31.6 ohm-1 = 0.0316 ohm-1 Specific conductance = conductance × cell cons...
(c) 1 × 1010 Explanation: Using the relation, 2s.png or Kc = 1 × 1010
(a) 90.1 Ohm-1cm2 Explanation: Because at infinite dilution the equivalent conductance of strong electrolytes furnishing same number of ions is sa...
(c) E1 > E2 Explanation: Using the relation 2s.png
(c) H2, Br2 and NaOH Explanation: NaBr ⇌ Na+ + Br- At cathode: 2H2O + 2e → H2 + OH- At cathode: Na+ + OH- → NaOH Br- → Br + e- At anode: B...
(b) 3F Explanation: MnO-4 + 4H+ + 3e- → MnO2 + 2H2O So, 3F of charge will be required to reduce 1 mole of MnO-4.
(b) Pt(s) | H2(g) 1 bar | 1 M HCl(aq) | 1MAg+(aq)|Ag(s) Explanation: In the given reaction 2AgCl(s) + H2(g) 1 bar →2HCl(aq) + 2Ag(s) Silver is...
(c) Cations move toward copper electrode. Explanation: Daniel cell is an electrochemical cell in which Cu acts as cathode and Zn acts as an anode....
(a) 30 s Explanation: Al3+ + 3e- → Al 1 mole requires = 3 × 96500 coulomb 1 millimole (10–3 mole) requires = 3 × 96500 × 10–3 C we know th...
(c) 2H2(g) + O2(g) → 2H2O(l) Explanation: Reaction used in fuel cell is 2H2(g) + O2(g) → 2H2O(l) At anode: [H2(g) → 4H+(aq) + 2e] x 2 At cat...
(b) 6 ×96500 coulomb Explanation: Cr2O2-7 + 14H+ + 6e- → 2Cr3+ + 7H2O For reducing one mole of Cr2O2-7, charge required = 6 × 96500 coulomb.
(c) Hg Explanation: Hg is lower than hydrogen on the electrochemical series. So, mercury is incapable of displacing hydrogen from dilute acids.
(d) Graphite Explanation: Though sodium and potassium are metals and show electrical conductance but graphite has more conductance due to presence...