Calculate the pH of a solution at 25.0 °C that contains 1.94 × 10-10 M hydronium ions.

To calculate the pH of a solution, you need to know the concentration of hydronium ions ([H3O+]). The pH is defined as the negative logarithm (base 10) of the hydronium ion concentration. The formula for calculating pH is:

pH = -log[H3O+]

In this case, the concentration of hydronium ions is given as 1.94 × 10^(-10) M. To find the pH, let's plug the value into the formula:

pH = -log(1.94 × 10^(-10))

Now, we can use a scientific calculator to evaluate this expression. Taking the negative logarithm of the concentration gives the pH value.

Using a calculator, the pH of the solution is approximately 9.71.

So, at 25.0 °C, the pH of the solution with a hydronium ion concentration of 1.94 × 10^(-10) M is approximately 9.71.

I think I did this above.