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The charge in coulombs that a battery produces when it discharges 250 A for 15.0 s, expressed in scientific notation is a.bc x 10d C. The values of a, b, c and d are

In an electrochemical cell, 150 C of charge is transferred in 1.5 min. The electric current is determined to be _________Answer A. 

The time to transfer 1.25 x 103 C using a current of 7.00 A is_____ Answermin 

The time to deposit 15.0 g of silver from a silver nitrate solution using a 6.00 A current is__________ Answer__________minutes.

make sure the answers are rounded  correctly

6 years ago

Answered By An B

Hi! In this question, you can use Faraday's First Law: Q=I x t with 

Q is the amount of electric charge (C)

I is the current (A)

t is the time (s)

 

Applying the formula,

Answer A= I = Q/t =150/(1.5 x 60) = 1.67 (A)

 

Answer B= t = Q/I = (1.25 x 10^3)/7 = 178.57 (s) = 178.57/60 (mins) = 2.98 (mins)

 

Answer C. You have to write the chemical reaction (since there is one happening here).

Ag(s) --> Ag+(aq) + 1e-

nAg(s)= nAg+(aq)=15/107.87=0.139 (mol)

ne- = nAg+(aq)= 0.139 (mol)

We use this equation: Q=n x F= I x t (with F is the Faraday's constant)

--> t= (n x F)/I = (0.139 x 96,485.3365)/6 = 2235.24 (s)

--> t= 2235.24/60 = 37.25 (mins)