Step 1: Write the half-reaction for the production of magnesium.
Magnesium ions (Mg2+) gain two electrons to form solid magnesium (Mg).
Mg2++2e−→Mg
Step 2: Calculate the total charge (Q) passed through the cell.
The current (I) is 500 amperes and the time (t) is 24 hours.
First, convert time to seconds:
t=24hours×60minutes/hour×60seconds/minute=86400 s
Now, calculate the charge:
Q=I×t
Q=500A×86400s=43200000 C
Step 3: Calculate the moles of electrons (ne) transferred.
Using Faraday's constant (F=96500 C/mol):
ne=FQ
ne=96500C/mol43200000C≈447.668 mol
Step 4: Determine the moles of magnesium (nMg) produced.
From the half-reaction, 2 moles of electrons are required to produce 1 mole of magnesium.
nMg=2ne
nMg=2447.668mol≈223.834 mol
Step 5: Calculate the mass of magnesium (mMg) produced.
The molar mass of magnesium (Mg) is 24 g/mol.
mMg=nMg×Molar Mass of Mg
mMg=223.834mol×24g/mol=5372.016 g
Step 6: Convert the mass from grams to kilograms.
mMg=1000g/kg5372.016g≈5.372 kg
The mass of magnesium produced is 5.372kg.
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