solution is made by diluting 22 mL of 4.2 M HCl until the final volume of the solution is 1.75 L. What is the pH? Recall how we find a molarity after a dilution.
First, we need to calculate the new molarity of the solution after dilution.
We use the formula for dilution:
M1V1 = M2V2
Where:
M1 = initial molarity (4.2 M)
V1 = initial volume (22 mL = 0.022 L)
M2 = final molarity
V2 = final volume (1.75 L)
Plugging in the values:
4.2 M * 0.022 L = M2 * 1.75 L
M2 = (4.2 M * 0.022 L) / 1.75 L
M2 = 0.0531 M
Now that we have the new molarity of the solution, we can calculate the pH by using the formula:
pH = -log[H+]
Since HCl is a strong acid, it completely dissociates in water to form H+ ions. Therefore, the concentration of H+ ions is equal to the concentration of HCl in the solution.
pH = -log(0.0531)
pH = 1.28
Therefore, the pH of the solution after dilution is 1.28.