To calculate the quantity of electricity required, we will use Faraday's laws of electrolysis. We need the molar mass of copper and Faraday's constant. We will assume copper is in the +2 oxidation state (Cu²⁺), which is common in copper compounds.
Step 1: Determine the molar mass of copper and Faraday's constant.
• Molar mass of copper (MCu) = 63.5 g/mol
• Faraday's constant (F) = 96485 C/mol e⁻
Step 2: Write the half-reaction for the liberation of copper.
Assuming copper is in the +2 oxidation state, the reduction half-reaction is:
Cu2+(aq)+2e−→Cu(s)
This reaction shows that 2 moles of electrons are required to liberate 1 mole of copper.
Step 3: Calculate the number of moles of copper to be liberated.
Given mass of copper (m) = 10 g.
Number of moles (nCu) = molarmassmass
nCu=63.5g/mol10g
nCu≈0.15748 mol
Step 4: Calculate the total moles of electrons required.
From the half-reaction, 2 moles of electrons are needed per mole of copper.
Moles of electrons (ne) = nCu×2
ne=0.15748mol×2
ne≈0.31496 mol e⁻
Step 5: Calculate the quantity of electricity (charge) in coulombs.
Quantity of electricity (Q) = ne×F
Q=0.31496mole−×96485 C/mol e⁻
Q≈30398.9 C
Rounding to three significant figures:
Q≈30400 C
The quantity of electricity required is:
30400C
What's next?