Question:

$pH$ of $0.005 M$ calcium acetate $\left( p K_{a}\right.$ of $CH _{3} COOH =4.74$ ) is :

Updated On: Jul 28, 2022
  • 7.04
  • 9.37
  • 9.26
  • 8.37
Hide Solution
collegedunia
Verified By Collegedunia

The Correct Option is D

Solution and Explanation

$0.005 \,M$ calcium acetate $(CH_3COO)_2Ca$ $\underset{0.005\,M}{(CH_3COO)_2Ca} \rightarrow Ca^{2+} + \underset{2\times 0.005 = 0.01)}{2CH_3COO^-}$ $\therefore [CH_3COO^-] = 0.01 \,M$ $CH_3COO^- + H_2O {<=>} CH_3COOH + \underset{\text{Alkaline}}{OH^-}$ $pH = 7 + \frac{pK_a}{2} + \frac{log \,C}{2}$ $= 7 + 2.37 + \frac{log\,0.01}{2}$ $= 7 + 2.37 - 1 = 8.37$
Was this answer helpful?
0
0

Top Questions on Buffer Solutions

View More Questions

Concepts Used:

Buffer solutions

The buffer solution is a solution that is able to maintain its Hydrogen ion concentration (pH) with only minor changes on the dilution or addition of a small amount of either acid or base. They are used in fermentation, food preservatives, drug delivery, printing, the activity of enzymes and many more.

Buffer solutions are aqueous solutions containing a weak acid and its salt - acid buffer or a weak base and its salt - base buffer.

Types of Buffer Solution

Acidic Buffers

These solutions are used to maintain acidic environments. Also, it has acidic pH and is prepared by mixing a weak acid and its salt with a strong base. An aqueous solution of an equal concentration of acetic acid and sodium acetate has a pH of 4.74.

Alkaline Buffers

These solutions are used to maintain basic conditions. It has a basic pH and is prepared by mixing a weak base and its salt with strong acid. The aqueous solution of an equal concentration of ammonium hydroxide and ammonium chloride has a pH of 9.25.