Acids ionize to form hydronium ions (hydrated hydrogen ions) and a negative ion:
HNO3 + H2O ---------> H3O+(aq) + NO3-(aq)
There are probably more than just one water molecule associated with the hydrogen ion, but water takes an active part in the making of the hydronium ion. There are few ions present in the pure nitric acid. The pH depends on the concentration of the hydronium ions in the solution and is calculated by: pH = - log [H3O+], the negative log of the molarity (strictly speaking the activity) of the hydronium ions.
HNO3 + H2O ---------> H3O+(aq) + NO3-(aq)
There are probably more than just one water molecule associated with the hydrogen ion, but water takes an active part in the making of the hydronium ion. There are few ions present in the pure nitric acid. The pH depends on the concentration of the hydronium ions in the solution and is calculated by: pH = - log [H3O+], the negative log of the molarity (strictly speaking the activity) of the hydronium ions.