First understand that both sulfuric acid and sodium hydroxide are a strong acid and strong base respectively, therefore both molecules will completely dissociate into H+ ions and OH- ions.
Now also note that for every H+ ion present an equal amount of OH- ions is required in order to neutralize them. So find out how much H+ ions there are then we will know how many OH- ions are required. Finally, use equation M = mol/L to determine the desired molar concentration.
H2SO4:
V = 150 mL = 0.150 L
M = 0.05 M
mol = VM = (0.150 L)(0.05 M) = 0.0075 mol H2SO4
Note: For every molecule of H2SO4 that dissociates we get 2 H+ ions, in other words we get 2 mols of H+ for every mol of H2SO4.
0.0075 mol H2SO4 * (2 mol H+ / 1 mol H2SO4) = 0.0150 mol H+
mol H+ = mol OH-
mol OH- = 0.0150 mol
NaOH:
V = 300.0 mL = 0.300 L
M = mol/L
M = 0.0150 mol /0.300 L = 0.05 M
M (NaOH) = 0.05 M [Answer]
Note: NaOH only forms one mole of OH- ions for every one mol of NaOH so no further calculation had to be done to compensate.
