Neutralization and Concentration

Question

Write the balanced neutralization reaction that occurs between H₂SO₄ and KOH in aqueous solution. Phases are optional.

neutralization reaction: _______

Suppose 0.550 L of 0.500 M H₂SO₄ is mixed with 0.500 L of 0.200 M KOH. What concentration of sulfuric acid remains after neutralization?

concentration: _______

Answer 1

H2SO4 + 2KOH ==> K2SO4 + 2H2O ... balanced equation

moles H2SO4 = 0.550 L x 0.500 mol / L = 0.275 mols H2SO4 present

moles KOH = 0.500 L x 0.200 mol / L = 0.100 moles KOH

Since the balanced equation tells us that it takes 2 moles KOH for every 1 mol H2SO4, clearly there isn't enough KOH to react with all of the H2SO4. So, KOH is limiting and will run out, leaving H2SO4 left over.

moles H2SO4 used up = 0.100 mols KOH x 1 mol H2SO4 / 2 mols KOH = 0.0500 mols H2SO4 used

moles H2SO4 left over = 0.275 mols - 0.0500 mols = 0.225 mols H2SO4 left over

Final volume = 0.550 L + 0.500 L = 1.05 L

[H2SO4] after reaction = 0.225 mols / 1.05 L = 0.214 M