Question
When 750 mL of 0.5 M HCl is mixed with 250 mL of 2 M NaOH solution, the value of pH will be
pH = 7
pH > 7
pH < 7
pH = 0
Solution
B.
pH > 7
nHCl = MHCl x VHCl and nNaOH = MNaOH x VNaOH
where n = number of moles
M = molarity, V = volume
∴ nHCl = 0.5 x 750 = 375 milimoles
nNaOH = 2.0 x 250 = 500 milimoles
∵ nNaOH > nHCl
The solution is basic and has pH > 7
