How many grams of All do you need to take to react with Y (iodine) to make 15 grams of aluminum iodide.

According to the condition of the problem, we compose the equation:
2Al + 3J2 = 2AlJ – redox reaction, aluminum iodide was obtained;
Let’s calculate the molar masses of substances:
M (Al) = 26.9 g / mol;
M (AlJ) = 153.8 g / mol.
Let us determine the amount of moles of aluminum iodide, if the mass is known:
Y (AlJ) = m / M = 15 / 153.8 = 0.09 mol.
Let’s make the proportion:
X mol (Al) – 0.09 mol;
-2 mol – 2 mol from here, X mol (Al) = 2 * 0.09 / 2 = 0.09 mol.
Find the mass of aluminum:
m (Al) = Y * M = 0.09 * 26.9 = 2.42 g.
Answer: the reaction requires aluminum weighing 2.42 g.