Alexia L. answered 06/29/25
Tufts Pre-Med | Passionate STEM Tutor Specializing in Chem
We’re given two tasks:
1. Write the balanced neutralization reaction between sulfuric acid (H₂SO₄) and potassium hydroxide (KOH).
2. Calculate the concentration of sulfuric acid remaining after mixing specific volumes and concentrations of each solution.
Step 1: Understand What a Neutralization Reaction Is
A neutralization reaction occurs when an acid and a base react to form water and a salt.
- H₂SO₄ is a diprotic acid, meaning it can donate 2 protons (H⁺).
- KOH is a strong base, and each KOH molecule provides 1 hydroxide ion (OH⁻).
So to neutralize all the H⁺ from one H₂SO₄ molecule, we need 2 KOH molecules.
Balanced equation:
H₂SO₄ + 2KOH → K₂SO₄ + 2H₂O
Tip: Always check the number of hydrogen ions your acid can donate and how many OH⁻ your base provides!
Step 2: Convert Volume to Moles
Use the formula: moles = molarity × volume
- H₂SO₄: 0.550 L × 0.500 mol/L = 0.275 mol
- KOH: 0.500 L × 0.200 mol/L = 0.100 mol
Tip: Make sure units cancel out correctly. L × mol/L gives mol!
Step 3: Determine the Limiting Reactant
From the balanced equation:
1 mol H₂SO₄ reacts with 2 mol KOH
So if we have 0.100 mol KOH, we need:
0.100 / 2 = 0.050 mol H₂SO₄
We have 0.275 mol H₂SO₄, so KOH is the limiting reactant.
Only 0.050 mol of H₂SO₄ will be used up.
Remaining H₂SO₄: 0.275 - 0.050 = 0.225 mol
Step 4: Find the Final Concentration of H₂SO₄
- Remaining H₂SO₄: 0.225 mol
- Total volume: 0.550 L + 0.500 L = 1.050 L
Concentration = 0.225 mol / 1.050 L = 0.214 M
Final Answers Recap
Balanced Reaction: H₂SO₄ + 2KOH → K₂SO₄ + 2H₂O
Concentration of H₂SO₄ remaining: 0.214 M