Answers by visitors named: slime xd

HNO3 is a strong acid; it ionizes 100%. moles HNO3 = grams/molar mass. 0.63/63=0.01 M HNO3 = moles/L soln. 0.01/1=0.01 pH = -log(M HNO3). -log(0.01) = 2