Respuesta :
The days it take to deposit the gold on both side of two earring if the current is 0.013 A is 32 days.
Earing is circular disc having radius 4.00 cm and thickness of gold plating is 0.25 mm which means that plating of gold is like cylinder.
Volume of gold on one side
Volume of gold plating = π × (radius) ^2 × width
By substituting all the values, we get
= 3.14 × 4 × 0.025cm
= 0.314 cm^2
Given,
density of gold = 19.3 g/cm^3
Calculation of mass of gold deposited on one side
Density = mass/volume
19.3 = mass/ 0.314
Mass = 19.3 × 0.314
= 6.06 g
Cathode reaction
(Au+3) + 3e- ----- Au
From chemical reaction we noticed that 3 mol. of e- reacts with 1 mol of Au3+ to form 1 mol of Au.
Calculation of charge
Charge passed to deposit 6.06g of gold can be calculated as
6.06 ×3 × 9.65× 10^4/ 196.97
= 8.91 × 10^3 C
Calculation of time
Time = charge/ current
= 8.91 × 10^3 /(0.013 × 3600 × 24)
= 7.93 days.
The time required for plating one side = 8 days
Two earing have four faces
Time for plating four surfaces = 8 × 4
= 32 days.
Thus, we calculated that the days it take to deposit the gold on both side of two earring if the current is 0.013 A is 32 days.
learn more about current:
https://brainly.com/question/16595375
#SPJ4
