A classroom experiment was set up to simulate the industrial extraction of zinc metal from an aqueous solution of zinc ions by electrolysis - VCE - SSCE Chemistry - Question 7 - 2009 - Paper 1

To determine the electric current supplied during electrolysis, we can use the following steps:

1. Calculate the moles of zinc produced:

   The molar mass of zinc (Zn) is approximately 65.4 g/mol. Thus, for 0.900 g of zinc:

   $ext{moles of Zn} = \frac{0.900 ext{ g}}{65.4 ext{ g/mol}} = 0.01376 ext{ mol}$

2. Determine the number of electrons transferred (n):

   From the half-reaction, each mole of Zn produces 2 moles of electrons:

   $n = 2 imes 0.01376 ext{ mol} = 0.02752 ext{ mol e^-}$

3. Calculate the total charge (Q):

   Using Faraday's constant (F = 96500 C/mol), the total charge can be calculated as:

   $Q = n imes F = 0.02752 ext{ mol}(96500 ext{ C/mol}) = 2656.00 ext{ C}$

4. Calculate the current (I):

   The time (t) is given as 30.0 minutes (or 1800 seconds):

   $I = \frac{Q}{t} = \frac{2656 ext{ C}}{1800 ext{ s}} = 1.477 ext{ A}$

5. Express the answer in appropriate significant figures:

   The final answer, rounded to three significant figures, is:

   $I = 1.48 ext{ A}$