A student titrated an unknown hydrochloric acid solution with a 0.115 M sodium hydroxide solution. They measured 8.00 mL of acid and it took 9.68 mL of the sodium hydroxide solution to reach the endpoint. Using the balanced equation that moles of acid equals moles of base, and the formula relating molarity, moles, and volume, the molarity of the hydrochloric acid solution was calculated to be 0.139 M.