If pK_(a) of value of acid is 6.4, then what should be the ratio between salt to acid concentration to prepared a buffer solution of pH = 5.4?
Correct answer: B. 1 : 10
- A. 1 : 1
- B. 1 : 10
- C. 10 : 1
- D. 1 : 2
Explanation
To determine the ratio of salt to acid concentration for the buffer solution, apply the Henderson-Hasselbalch equation: pH = pKa + log([Salt]/[Acid]). Given pH = 5.4 and pKa = 6.4, subtracting gives: 5.4 = 6.4 + log([Salt]/[Acid]) -1 = log([Salt]/[Acid]). Solving for the ratio: [Salt]/[Acid] = 10-1 = 1/10, or 1:10. Therefore, the correct ratio is 1:10, which supports the buffer solution at a pH of 5.4. The other options either suggest equal concentrations or incorrect ratios that would not achieve the desired pH.
Last updated
About Acids, Bases and Salts
Acid and base behaviour is explained through the Bronsted-Lowry transfer of protons and the Lewis donation or acceptance of electron pairs. The topic includes pH, pOH, ionisation and water equilibrium, plus salt formation and hydrolysis, where a salt solution may become acidic, basic or neutral.
Practise Acids, Bases and Salts
314 free Acids, Bases and Salts MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Chemistry questions like this
Chemistry is on 12 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
All of the following are postulates of Arrhenius theory of ionization except
Which of the following aqueous solution will be basic?
A start of reaction, concentration of reactants are on
An acid that can act as an oxidizing, dehydrating and acid-producing agent is
Which of the following compounds is the strongest Bronsted acid