Answer:
514.65 g of Zn
Step-by-step explanation:
Zinc metal reacts with copper ions in a salt of copper to form copper metal and zinc (ii) salt.
The equation for the reaction is;
Zn(s) + Cu²⁺(aq) → Zn²⁺(aq) + Cu(s)
we are required to calculate the mass of Zinc needed
Step 1: Number of moles of copper
The mass of copper metal produced is 500.0 grams
We can get the number of moles of copper,
Molar mass of copper = 63.55 g/mol
But; Number of moles = Mass ÷ Molar mass
Therefore;
Moles of copper = 500.0 g ÷ 63.55 g/mol
= 7.868 moles
Step 2: Moles of Zinc
From the reaction 1 mole of Zinc metal reacts with a salt of copper (ii) to produce 1 mole of copper.
Therefore, the ratio of Zn : Cu is 1 : 1
Hence;
Moles of zinc will be 7.868 moles
Step 3: Mass of Zinc metal
Moles of Zn = 7.868 moles
Molar mass of Zn = 65.41 g/mol
But; Mass = number of moles × molar mass
Thus;
Mass of Zn = 7.868 moles × 65.41 g/mol
= 514.65 g
Therefore, the mass of Zn metal needed is 514.65 g