How many moles of gold are deposited on the electrode in 10.98 hours?

AI Thread Summary
To determine the current in an electrolytic cell where 3.32 kg of gold is deposited over 10.98 hours, first convert the mass of gold to grams, resulting in 3320 grams. Using the molar mass of gold, approximately 197 g/mol, calculate the number of moles by dividing the mass by the molar mass, yielding about 16.8 moles. Each mole of gold corresponds to Avogadro's number of atoms, each carrying one elementary charge. Finally, use the total charge and the time to find the current using the formula current = charge/time. This process effectively calculates the current based on the mass of gold deposited.
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Homework Statement



If 3.32 kg of gold is deposited on the negative electrode of an electrolytic cell in a period of 10.98 h, what is the current in the cell in this period?Assume that each gold ion car ries one elementary unit of positive charge.

Homework Equations



i don't know what equation to use all i know is current= charge/time



The Attempt at a Solution


i couldn't find the solution because i didnt know how to use the mass??
 
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Are you sure that it was 3.32 kg ? A big piece of gold.

Anyway: Find the molar mass of gold (about 197 g/mol) . Get the moles of gold from the given mass. Multiply by Avogadro number: you get the number of gold atoms. Each carries an elementary charge -how much is it? You know the charge and time, easy to get the current.

ehild
 
Last edited:
yes it was 3.32 and now ill try working it out how you said
 
the atomic mass is 196.97 bt how do you get it to moles?
 
This value means that the mass of one mole gold is 196.97 g.
If 196.97 g is one mole, how many moles are in 3.32 kg?

ehild
 
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