English
Karnataka Board PUCPUC Science Class 11

If 0.561 g of KOH is dissolved in water to give 200 mL of solution at 298 K. Calculate the concentrations of potassium, hydrogen and hydroxyl ions. What is its pH?

Advertisements
Advertisements

Question

If 0.561 g of KOH is dissolved in water to give 200 mL of solution at 298 K. Calculate the concentrations of potassium, hydrogen and hydroxyl ions. What is its pH?

Short/Brief Note
Advertisements

Solution

`["KOH"_("aq")] = 0.561/(1/5) "g"/"L"`

= 2.805 g/L

`= 2.805 xx 1/56.11 "M"`

= 0.05 M

`"KOH"_("aq") -> "K"_("aq")^+ + "OH"_(("aq"))^-`

`["OH"^-] = 0.05 "M" = ["K"^+]`

`["H"^+] ["H"^-] = ["K"^+]`

`["H"^+] "K"_"w"/(["OH"^-])`

`= 10^(-14)/0.05 = 2xx 10^(-13) "M"`

`therefore "pH" = 12.70`

shaalaa.com
  Is there an error in this question or solution?
Chapter 6: Equilibrium - EXERCISES [Page 237]

APPEARS IN

NCERT Chemistry - Part 1 and 2 [English] Class 11
Chapter 6 Equilibrium
EXERCISES | Q 7.57 | Page 237
Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×