Answer:
a) 0.38 mol.
b) 0.38 mol.
c) 26.94 g.
Step-by-step explanation:
- For the balanced equation:
2KI(aq) + Cl₂(g) → 2KCl(aq) + I₂(g),
It is clear that 2 mol of KI react with 1 mol of Cl₂ to produce 2 mol of KCl and 1 mol of I₂.
a) How many moles of I₂ are produced?
- Firstly, we need to calculate the no. of moles of 8.5 L of produced I₂:
It is known that every 1.0 mol of any gas occupies 22.4 L at STP conditions.
Using cross multiplication:
1 mol of I₂ occupies → 22.4 L, at STP.
??? mol of I₂ occupies → 8.5 L, at STP.
∴ The no. of moles of I₂ produced = (1 mol)(8.5 mol)/(22.4 L) = 0.38 mol.
b) How many moles of Cl₂ are used?
Using cross multiplication:
1 mol of Cl₂ produces → 1 mol of I₂, from stichiometry.
∴ 0.38 mol of Cl₂ produces → 0.38 mol of I₂.
So, the no. of moles of Cl₂ are used = 0.38 mol.
c) How many grams of Cl₂(g) are used?
∴ The "no. of grams" of Cl₂(g) are used = (no. of moles of Cl₂)(molar mass of Cl₂) = (0.38 mol)(70.9 g/mol) = 26.94 g.