If it requires 18.2 ml of 0.45 molar barium hydroxide to neutralize 38.5 ml of nitric acid, solve for the molarity of the nitric acid solution. show all the work used to solve this problem

The moles of OH- ions from the Ba(OH)2 must equal the moles of H+ ions from the HNO3 in order for them to neutralize. You must multiply volume (in liters) by the molar to get number of moles. There is 0.90 molar of OH- because there is twice as many OH- as there is Ba(OH)2. The molarity of H+ is unknown.

Let X be the unknown molarity

(0.0182 L)(0.90 M) = (0.0385 L)(X M)

X = 0.43 M (2 significant figures)

So the molarity of H+ ions, and therefore HNO3 is 0.43 M

the answer is d. 74.02