The authoritative public forum
  for Metal Finishing 1989-2024
  

  -----

Where is "mechanical work" going on in electroplating?

DEAR SIR,
I AM A STUDENT AND MY PROJECT IS ELECTROPLATING. MY TEACHER ASK ME THAT IN ELECTROPLATING WHERE IS MECHANICAL WORK IS GOING ON.

MUAHMMAD A
STUDENT - PAKISTAN
2007

I posted your question as much for my own education as yours, Muahmmad :-)

You must carefully read the definition of mechanical work in your text book or whatever source you are supposed to use. But my interpretation is that you have not increased the object's kinetic energy and therefore you have not done work. My interpretation is also based on the parallel that heat conduction is specifically excluded as not being mechanical work, and the electricity consumed in plating can be expressed in thermal units.

Now if you had a block of metal in a plating beaker, and you gave the beaker a swat so it went sliding along the lab table, and you electroplated the block while it was moving, so that it's mass increased, you would increase the kinetic energy of the metal block and thus be doing mechanical work on it, while doing negative work on the anode or plating solution which lost mass :-)

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007

---

Mechanical work is done whenever the parts are moved, either by machine or people. In electroplating, mechanical work is also done when air agitation is used - the air needs to be pumped into the solution, where it moves the liquid around.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2007

---

2007

A strange question. But to give it a try...

Ions have mass and move through the solution with finite velocity. Therefore they have kinetic energy.

Or, to put another way, mass moves from the anode to the cathode during the plating time.

In heat conduction or radiation, there is no mass transfer but there is in convection.

Trevor's suggestions are ok but are not necessary for the electroplating process.

Geoff Smith
Hampshire, England