Answer:
The answer to your question is 0.79 moles of SnCl₂
Explanation:
Data
moles of SnCl₂ = ?
mass of FeCl₃ = 85.3 g
excess Sn
Balanced chemical reaction
2 FeCl₃ + 3 Sn ⇒ 3 SnCl₂ + 2 Fe
Process
1.- Convert the mass of FeCl₃ to moles
Molar mass of FeCl₃ = 56 + (35.5 x 3)
= 56 + 106.5
= 162.5 g
Use proportions to find the moles of FeCl₃
162.5 g -------------------- 1 mol
85.3 g ------------------- x
x = (85.3 x 1) / 162.5
x = 0.525 moles
2.- Find the number of moles SnCl₂
2 moles of FeCl₃ ----------------- 3 moles of SnCl₂
0.525 moles ----------------- x
x = (0.525 x 3) / 2
x = 0.79 moles of SnCl₂
