Question

Calculate the pH of milk with a hydrogen ionconcentration of 4.25 x 10^-7 mol dm-3. Show all steps ofyour calculations and include the correct units

Answer 1

6.37.

Step-by-step explanation:

What is given?

[H (+)] = 4.25 x 10⁻⁷ mol/dm³

Step-by-step solution:

First, let's see the formula to calculate the pH based on the hydrogen ion concentration (H (+)):

`pH=-log\lbrack H^+].`

*Logarithm must be in base 10!

Our given concentration of hydrogen ion is 4.25 x 10⁻⁷ mol/dm³. Remember that the units of concentration must be in M (mol/L) but in this case, 1 dm³ equals 1 L, so based on this, we have that:

`4.25\cdot10^(-7)(mol)/(dm^3)=4.25\cdot10^(-7)(mol)/(L).`

So, we can replace this value in the formula of pH:

`pH=-log\lbrack4.25\cdot10^(-7)]\approx6.37.`

The pH of milk would be 6.37 which means that is slightly acid (weak acid).