finding the pH of a acid

Question

0.0064 g of hydronitric acid is dissolved in 50 mL of water. What is the pH?

Answer 1

As far as I know, there is no acid commonly known as hydronitric acid. I'll assume this to be simply nitric acid (HNO₃) which is a strong acid and it ionizes completely.

molar mass HNO₃ = 63.0 g / mole

moles HNO₃ present = 0.0064 g x 1 mol / 63 g = 0.000102 moles

[H⁺] = 0.000102 moles / 0.050 L = 0.00203 M

pH = -log [H⁺] = -log 0.00203

pH = 2.69

Answer 2

convert mass to moles, divide by volume in Liters, plug into -log[H+] formula, get pH.