How many moles of HNO3 are present if 4.90×10−2 mol of Ba(OH)2 was needed to neutralize the acid solution?

0.098 moles of HNO₃ are present if 4.90× mol of Ba(OH)₂ was needed to neutralize the acid solution

Explanation:

1 mole of Ba(OH)₂ contains 2 moles of OH- ions.

Hence, 0.049 moles of Ba(OH)2 contains x moles of OH- ions.

cross multiplying, we have

1 mole * x mole = 2 moles * 0.049 mole

x mole = 2 * 0.049 / 1

x mole =  0.098 moles of OH- ions.

1 mole of OH- can neutralize 1 mole of H+

Therefore, 0.098 moles of HNO₃ are present if 0.049 moles of Ba(OH)₂ was needed to neutralize the acid solution.