pH of Nitric Acid (HNO_{3}) Solution | Online Calculator

Nitric acid is a strong oxidizing acid
and it completely dissociates to the hydronium ions and nitrate ions in water
to show strong acid characteristics. In this tutorial, we are looking to study how to calculate pH of aqueous nitric acid
solutions.

In this tutorial we will cover following sections.

pH values of different concentrations aqueous HNO_{3} solutions

Two online calculators to calculate pH value of HNO_{3}

Solving a problem of how to calculate pH of HNO_{3}

pH values of different concentrations aqueous HNO_{3} acid solutions

Concentration (mol dm^{-3})

pH

0.1

1

0.05

1.30

0.01

2

0.005

2.30

0.001

3

1

0

Online pH Calculator for HNO_{3} acid

According to the data you know, you can use a suitable calculator to calculate pH value.

When concentration is known in mol dm^{-3}

you can enter the concentration of HNO_{3} acid in mol dm^{-3} and check the pH value.

Answer

Note: This online calculation is not suitable for very dilute solutions of HNO_{3} (such as 0.0000005 mol dm^{-3}) because,
those solutions give very low H^{+} ion concentration. In those cases, pH value is very close to the neutral value
of seven.

Calculate pH when density and weight fraction (w/w %) of HNO_{3} solution is known

Answer

Calculate pH of HNO_{3} using the pH equation

Because HNO_{3} is a strong acid, it dissociates completely to H^{+} and NO_{3}^{-} ions in the water.

HNO_{3} → H^{+} + NO_{3}^{-}

According to the stoichiometric ratios, H^{+} concentration equals to the HNO_{3} concentration. Therefore, we can directly
substitute HNO_{3} concentration to pH calculation equation.

pH = -log_{10}[H^{+}_{(aq)}]

We can write above equation for HNO_{3} as below.

pH = -log_{10}[HNO_{3}_{(aq)}]

pH of 0.1 mol dm^{-3} HNO_{3} solution

pH = -log_{10}[0.1]

pH = 1

You can see, 0.1 mol dm^{-3} HNO_{3} acid solution is strong acidic solution because pH value is well below seven.