Calculate the mass of nitric acid that must be neutralized with potassium hydroxide to obtain

Calculate the mass of nitric acid that must be neutralized with potassium hydroxide to obtain 80g of a 20% potassium nitrate solution.

1. Let’s write down the equality of chemical interaction:

KOH + HNO3 = KNO3 + H2O.

2. Find the number of moles of the resulting potassium nitrate:

m (KNO3) = m (solution) * ω (KNO3) / 100% = 80 g * 20% / 100% = 16 g.

n (KNO3) = m (KNO3) / M (KNO3) = 16 g / 101 g / mol = 0.158 mol.

3. Using the equality of the chemical interaction, we calculate the number of moles and, as a result, the mass of the reacted nitric acid:

n (HNO3) = n (KNO3) = 0.158 mol.

m (HNO3) = n (HNO3) * M (HNO3) = 0.158 mol * 63 g / mol = 9.98 g.

Result: m (HNO3) = 9.98 g.