When an aluminum oxide weighing 10 grams interacts with potassium hydroxide

When an aluminum oxide weighing 10 grams interacts with potassium hydroxide weighing 12 grams, a salt is formed, calculate the weight of this salt.

Let’s compose the equation of the salt formation reaction – potassium aluminate.

Al2O3 + 2KOH = 2KAlO2.

Let’s find the number of moles of starting substances:

n (Al2O3) = m / Mr = 10/102 = 0.1 mol.

n (KOH) = m / Mr = 12/56 = 0.2 mol.

The amount of alkali will be in excess, so we calculate the mass of salt according to the lack:

n (Al2O3) = n (KAlO2) = 0.1 mol.

m (KAlO2) = n • Mr = 0.1 • 98 = 9.8 g.