A25.0-ml sample of an h2so4 solution requires 50.0 ml of 0.150 m naoh to completely react with the h2so4. what was the concentration (molarity, m) of the h2so4 solution?
h2so4(aq) + 2 naoh(aq) à na2so4(aq) + 2 h2o(l)

V( H₂SO₄) = 25.0 mL in liters = 25.0 / 1000 = 0.025 L
 M(H₂SO₄) = ?

V(NaOH) = 50.0 mL = 50.0 / 1000 = 0.05 L 
M(NaOH) = 0.150 M

number of moles NaOH :

n = M x V

n = 0.150 x  0.05 

n = 0.0075 moles of NaOH 

H₂SO₄(aq) + 2 NaOH(aq) = Na₂SO₄(aq) + 2 H₂O(l)

1 mole H₂SO₄ 2 mole NaOH
? mole H₂SO₄  0.0075 moles NaOH

moles = 0.0075 * 1 / 2

= 0.00375 moles of H₂SO₄

M(H₂SO₄) = n / V

M = 0.00375 /  0.025

= 0.15 M

hope this helps!

High-energy and unstable.