Question

A solution is made by mixing 0.05 ml of 1.0 m hcl with 999.95 ml of pure water. calculate the ph of the resulting solution (assume the total volume is 1.0 l).

Answer 1

The pH of the resulting solution is approximately 4.30.

Step-by-step explanation:

The pH of a solution can be calculated using the formula pH = -log[H+]. In this case, the solution is made by mixing 0.05 mL of 1.0 M HCl with 999.95 mL of pure water to make a total volume of 1.0 L. So, the molarity of HCl in the solution is:

Molarity = moles of solute / volume of solution

Moles of HCl = 1.0 M x 0.05 mL / 1000 mL/L = 0.00005 moles

Molarity = 0.00005 moles / 1.0 L = 0.00005 M

Now, we can calculate the pH:

pH = -log(0.00005)

pH ≈ 4.30

Answer 2

Hydrochloric acid or HCl is classified as a strong acid which means it dissociates into ions completely when in water. It ionizes into hydrogen ions and chloride ions. pH is a scale which measures the acidity or alkalinity of a solution. It is expressed as the negative logarithm of the concentration of hydronium ions or the hydrogen ions. To determine pH, we need to determine the concentration of the hydrogen ions. We do as follows:

moles H+ = 1.0 M HCl ( 0.00005 L ) ( 1 mol H+ / 1 mol HCl ) = 0.00005 mol H+
Concentration of H+ = 0.00005 mol H+ / 1.0 L = 0.00005 M

pH = -log [H+]
pH = -log [0.00005]
pH = 4.3