Answer:
32.3%
Step-by-step explanation:
Percent yield is defined as:
Actual yield (125.5g) / Theoretical Yield * 100
To find theoretical yield we have to find the moles of aluminium. As 2 moles of Al produce 2 moles of AlCl3, the moles of Al = Moles AlCl3.
With these moles we can find the mass assuming a 100% of yield (Theoretical Yield) as follows:
Moles Al = Moles AlCl3 (Molar mass Al = 26.98g/mol)
72g Al * (1mol / 26.98g) = 2.67 moles AlCl3
Mass AlCl3 (Molar mass: 133.34g/mol)
2.67 moles AlCl3 * (133.34g / mol) = 355.8g AlCl3
Percent Yield = 125.5g / 355.8g * 100 =
32.3%