Calculate the mass of the salt formed when draining 200 g of 10% hydrochloric
Calculate the mass of the salt formed when draining 200 g of 10% hydrochloric acid solution and 200 g of 20% potassium hydroxide solution.
1. Let’s compose the equation of the chemical reaction:
KOH + HCl = KCl + H2O.
2. Find the chemical amount of potassium hydroxide and hydrochloric acid:
m (KOH) = m (solution) * ω (KOH) / 100% = 200 g * 20% / 100% = 40 g.
n (KOH) = m (KOH) / M (KOH) = 40 g / 56 g / mol = 0.71 mol.
m (HCl) = m (solution) * ω (HCl) / 100% = 200 g * 10% / 100% = 20 g.
n (HCl) = m (HCl) / M (HCl) = 20 g / 36.5 g / mol = 0.55 mol.
3. Find the chemical amount, and then the mass of potassium chloride:
! HCl is in short supply.
n (KCl) = n (HCl) = 0.55 mol.
m (KCl) = n (KCl) * M (KCl) = 0.55 mol * 74.5 g / mol = 40.82 g.
Answer: m (KCl) = 40.82 g.