What will be the pH of the solution that results from the addition of 20mL of 0.01M Ca(OH)2 to 30mL of 0.01M HCl?
It is a strong acid-base reaction as HCl is a strong acid and Ca(OH)2 is a strong base
The net ionic reaction is
HCl is a strong acid thus
moles of HCl = moles of
Calculate no. of moles in 30mL of 0.01M HCl
0.0003moles of HCl will produce 0.0003moles of
Now calculate the number of moles in 20mL of 0.01M
As this is titrating of a strong acid with a strong base the addition of the base results in decrease in
0.0003mole - 0.0002mole = 0.0001mole of
You must now calculate the pH by using the moles and the total volume
But while calculating pH we must use the molarity and not mole.
For that we need to add both the volumes that is
20mL + 30mL = 50mL = 0.05L
= 0.002M of