Question

For a science experiment you need to electroplate zinc onto both sides of a very thin, 1.00 cm x 1.00 cm copper sheet. You want the zinc thickness to be 140 nm , and you know that the charge carriers in the ionic solution are divalent (charge 2e) zinc ions. The density of zinc is 7140 kg/m3 .If the electroplating apparatus operates at 1.40 A, how long (in seconds) will it take the zinc to reach the desired thickness?Please explain.

Answer 1

Answer:

Explanation:

volume of zinc electroplated =2 x 1 x 10⁻² x 1 x 10⁻² x 140 x  10⁻⁹ = 280 x 10⁻¹³ .m³³

mass of zinc = 280 x 10⁻¹⁴ x 7140 kg = 19.992 x10⁻⁹ kg.

charged required to electroplate 65 g of Zn is 2 x 96500C

Charged required to electroplate 9.996 x 10⁻⁹ kg = 2 x (96500000 / 65) x 19.992 x 10⁻⁹   =( 2 x 965 x 19.992/65) x 10⁻⁴ .

=593.6 x 10⁻⁴ .C

Q = I X t

593.6 x 10⁻⁴ = 1.4 t

t =( 593.6 / 1.4 )x 10⁻⁴ = 42.4 x 10⁻³ s = 42.4 ms.