How much aluminum is required to react with sulfur to obtain 0.1 mol of aluminum sulfide (Al2S3)?

Let’s compose the reaction equation and arrange the coefficients:

2Al + 3S = Al2S3

Let’s make a proportion, including the amount of substance in moles and coefficients in front of aluminum and aluminum sulfide.

2 = 1 (row of coefficients)

x = 0.1 (string of moles)

x = 0.1 * 2/1 = 0.2 mol (amount of aluminum substance)

Answer: 0.2 mol of aluminum is required.