Ionisation Constant Of Acid Base Salt

Q: -->Phosphoric acid ionizes in three steps, with their ionization...

Hint : \(\mathrm{K}_{a_1} >\mathrm{~K}_{\mathrm{a}_2}>\mathrm{K}_{\mathrm{a}_3} \) Explanation : (i) The overall ionization constant (K) is the product of the individual steps: \(K = K_{a_1} \times K_{a_2} \times K_{a_3}\) , so on taking log on both sides we will get \(\log \mathrm{K}=\log \mathrm{K}_{\mathrm{a}_1}+\log \mathrm{K}_{\mathrm{a}_2}+\log \mathrm{K}_{\mathrm{a}_3}\) hence it is correct. (ii) \(\text{H}_3\text{PO}_4\) is a stronger acid than \(\text{H}_2\text{PO}_4^{-}\) and \(\text{HPO}_4^{2-}\) . (iii) The ionization constant decreases with each successive step. This is because it becomes more difficult to remove a positively charged proton \(\text{H}^+\) from an increasingly negatively charged anion, hence \(\mathrm{K}_{a_1} >\mathrm{~K}_{\mathrm{a}_2}>\mathrm{K}_{\mathrm{a}_3} \) . (iv) There is no general relationship that defines \(K_{a_1}\) as the arithmetic mean of \(K_{a_2}\) and \(K_{a_3}\) . Therefore, A,B, and C are correct.

01

PYQ 2013

easy

chemistry ID: neet-201

The strongest acid among the following compounds is: 1. HClO 3 2. HClO 4 3. H 2 SO 3 4. H 2 SO 4

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02

PYQ 2015

easy

chemistry ID: neet-201

Aqueous solution of which of the following compounds is the best conductor of electric current? 1. Acetic acid, 2. Hydrochloric acid, 3. Ammonia, 4. Fructose,

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03

PYQ 2016

easy

chemistry ID: neet-201

The percentage of pyridine (C5H5N) that forms pyridinium ion (C5H5N+H) In A 0.10 M aqueous pyridine solution (Kb for C5H5N = 1.7 \times 10–9) is? 1. 0.0060% 2. 0.013% 3. 0.77% 4. 1.6%

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04

PYQ 2021

easy

chemistry ID: neet-202

The pK b of dimethylamine and pk a of acetic acid are 3.27 and 4.77 respectively at T (K). The correct option for the pH of dimethylammonium acetate solution is: 1. 7.75 2. 6.25 3. 8.50 4. 5.50

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05

PYQ 2025

medium

chemistry ID: neet-202

Phosphoric acid ionizes in three steps, with their ionization constant values respectively, while is the overall ionization constant. Which of the following statements are true for the ionization of phosphoric acid? A. B. is a stronger acid than and C. D. Choose the correct answer from the options given below : 1. B, C and D only 2. A, B and C only 3. A and B only 4. A and C only

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Ionisation Constant Of Acid Base Salt

High-Yield Trend

Questions
5 MCQs

Official Solution

Official Solution

Official Solution

Official Solution

Official Solution

1.	Acetic acid, $%5Cmathrm%7BC_%7B2%7D%20H_%7B4%7D%20O_%7B2%7D%7D$	2.	Hydrochloric acid, $%5Cmathrm%7BHCl%7D$
3.	Ammonia, $%5Cmathrm%7BN%20H_%7B3%7D%7D$	4.	Fructose, $%5Cmathrm%7BC_%7B6%7D%20H_%7B12%7D%20O_%7B6%7D%7D$

A.	$%5Clog%20%5Cmathrm%7BK%7D%3D%5Clog%20%5Cmathrm%7BK%7D_%7B%5Cmathrm%7Ba%7D_1%7D%2B%5Clog%20%5Cmathrm%7BK%7D_%7B%5Cmathrm%7Ba%7D_2%7D%2B%5Clog%20%5Cmathrm%7BK%7D_%7B%5Cmathrm%7Ba%7D_3%7D$
B.	$%5Cmathrm%7BH%7D_3%20%5Cmathrm%7BPO%7D_4$ is a stronger acid than $%5Cmathrm%7BH%7D_2%20%5Cmathrm%7BPO%7D_4%5E%7B-%7D$ and $%5Cmathrm%7BHPO%7D_4%5E%7B2-%7D%20.$
C.	$%5Cmathrm%7BK%7D_%7Ba_1%7D%20%3E%5Cmathrm%7B~K%7D_%7B%5Cmathrm%7Ba%7D_2%7D%3E%5Cmathrm%7BK%7D_%7B%5Cmathrm%7Ba%7D_3%7D$
D.	$%5Cmathrm%7BK%7D_%7B%5Cmathrm%7Ba%7D_1%7D%3D%5Cfrac%7B%5Cmathrm%7BK%7D_%7B%5Cmathrm%7Ba%7D_3%7D%2B%5Cmathrm%7BK%7D_%7B%5Cmathrm%7Ba%7D_2%7D%7D%7B2%7D$

1.	HClO₃	2.	HClO₄
3.	H₂SO₃	4.	H₂SO₄

Ionisation Constant Of Acid Base Salt

High-Yield Trend

Questions 5 MCQs

Official Solution

Official Solution

Official Solution

Official Solution

Official Solution

Questions
5 MCQs