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THROWING POWER IS INCREASED?

2003

I am a engineer and am attempting to answer some of the questions in an ASM course book in our library.

Could you please assist and explain how I solve this question? Thanks,

IN A STRIPPING TEST 2.476g (.087 oz.) OF NICKEL WERE REMOVED ELECTROLYTICALLY FROM A SPECIMEN WITH A SURFACE AREA OF 75 BY 150 mm (3 x 6 IN). THE THICKNESS OF THE NICKEL PLATE AND THE AMOUNT OF ELECTRICITY USED WERE, RESPECTIVELY:

A. 25 MICRO METERS, 8140 COULOMBS
B. 31.6 MICRO METERS, 8970 COULOMBS
C. .001 IN, 120.6 COULOMBS
D.1 MIL, 4.5 FARADAYS

MICHAEL FERRETTI
- SCIOTA, Pennsylvania, USA

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This is apparently a multiple-choice question where you have to figure out which answer is reasonable. You were given much more info than is needed, which might be what is confusing you.

You can find the answer with simple geometry without needing to know anything at all about electrochemistry. So, since you are an engineer, I know that you know at least one way to answer the problem.

On the other hand if you know the gram equivalent weight of nickel you can answer the question by Faraday's Law without concerning yourself about the geometry.

But we have no way of guessing how much you know about electrochemistry and consequently where to start to help you over the hurdle. Do you know what a coulomb is? A Faraday? An equivalent weight? Do you know what valence or oxidation state means? Do you know what Faraday's Law states? Do you know what a mil is? Tell us what terms are unfamiliar and then we can be of more help.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003