Molarity of HCl = 1 M
Volume of HCl = 30 mL = 30/1000 L = 0.03 L
Number of moles of HCl = Molarity * Volume = 1M * 0.03L = 0.03
mol
Now after addinng 200 mL of water, Volume becomes = 30mL+ 200
mL
                                                  Â
= 230 mL = 230/1000 L = 0.23 L
So,
New Molarity of HCl = number of moles / new Volume
                        Â
= 0.03 / 0.23
                        Â
=0.13 M
[H+] = 0.13 M
pH = -log [H+]
  = - log (0.13)
  = 0.88
Answer: 0.88
