Calculate the pH of a 0.0019 M HNO3 solution.
2.7
I would have one more place. The 2 comes from the characteristic. You are allowed 2 places in the mantissa so I would write it as 2.72.
To calculate the pH of a solution, including the 0.0019 M HNO3 solution in this case, you can use the formula:
pH = -log [H+]
In this formula, [H+] represents the concentration of hydrogen ions in the solution.
Given that HNO3 is a strong acid, it is completely dissociated in water, meaning that every molecule of HNO3 will release one H+ ion into the solution. Therefore, the concentration of H+ ions in the solution is equal to the concentration of the HNO3 solution.
For the 0.0019 M HNO3 solution, the concentration of H+ ions is 0.0019 M.
Now you can substitute this value into the formula:
pH = -log (0.0019)
Using a scientific calculator, take the logarithm of 0.0019 and multiply by -1 to get the pH:
pH ≈ 2.7