The time required to coat a metal surface of 80 cm 2 with 5 × 10-3 cm thick layer of silver (density .1.05 g cm -3) with a passage of 3 A current through a silver nitrate solution is

Question

The time required to coat a metal surface of 80 cm 2 with 5 × 10-3 cm thick layer of silver (density .1.05 g cm -3) with a passage of 3 A current through a silver nitrate solution is (A) 115 s (B) 125 s (C) 135 s (D) 145 s

Tardigrade Admin · Accepted Answer

Weight of Ag required =80 × 5 × 10-3 × 1.05 =0.42 g ( wt. =V × d) ∵ w=(E I t/96500) ∴ 0.42=(108 × 3 × t/96500) ; t=125 s

Q. The time required to coat a metal surface of $80 c m^{2}$ with $5 \times 1 0^{- 3} c m$ thick layer of silver (density $1.05 g c m^{- 3})$ with a passage of $3 A$ current through a silver nitrate solution is

$115 s$

$125 s$

$135 s$

$145 s$

Weight of Ag required $= 80 \times 5 \times 1 0^{- 3} \times 1.05$

$= 0.42 g (wt . = V \times d)$

$∵ w = \frac{E I t}{96500} ∴ 0.42 = \frac{108 \times 3 \times t}{96500}; t = 125 s$

Q. The time required to coat a metal surface of 80cm2 with 5×10−3cm thick layer of silver (density 1.05gcm−3) with a passage of 3A current through a silver nitrate solution is

115s

125s

135s

145s