Conductance

To find the dissociation constant ( $K_a$ ) of acetic acid, we need to use the relationship between molar conductivity and dissociation. Here is the step-by-step solution to find the dissociation constant:

Determine the limiting molar conductivity ( $%5CLambda%5E%5Ccirc_m$ ) of acetic acid:

The limiting molar conductivity of an electrolyte is the sum of the limiting molar conductivities of its constituent ions. For acetic acid, $CH_3COOH$ , it dissociates into $H%5E%2B$ and $CH_3COO%5E-$ .

%5CLambda%5E%5Ccirc_m%20%3D%20%5CLambda_%7BH%5E%2B%7D%5E%5Ccirc%20%2B%20%5CLambda_%7BCH_3COO%5E-%7D%5E%5Ccirc

Given, $%5CLambda_%7BH%5E%2B%7D%5E%5Ccirc%20%3D%20350%20%5C%2C%20S%20%5C%2C%20cm%5E2%20%5C%2C%20mol%5E%7B-1%7D$ and $%5CLambda_%7BCH_3COO%5E-%7D%5E%5Ccirc%20%3D%2050%20%5C%2C%20S%20%5C%2C%20cm%5E2%20%5C%2C%20mol%5E%7B-1%7D$ .

%5CLambda%5E%5Ccirc_m%20%3D%20350%20%2B%2050%20%3D%20400%20%5C%2C%20S%20%5C%2C%20cm%5E2%20%5C%2C%20mol%5E%7B-1%7D

Calculate the degree of dissociation ( $%5Calpha$ ) using the formula:

%5Calpha%20%3D%20%5Cfrac%7B%5CLambda_m%7D%7B%5CLambda%5E%5Ccirc_m%7D%20%3D%20%5Cfrac%7B20%7D%7B400%7D%20%3D%200.05

Use the degree of dissociation to find the dissociation constant $K_a$ :

K_a%20%3D%20c%20%5Calpha%5E2%20%3D%200.007%20%5Ctimes%20(0.05)%5E2

K_a%20%3D%200.007%20%5Ctimes%200.0025%20%3D%200.0000175%20%3D%201.75%20%5Ctimes%2010%5E%7B-5%7D%20%5C%2C%20mol%20%5C%2C%20L%5E%7B-1%7D

Therefore, the dissociation constant of acetic acid is $1.75%20%5Ctimes%2010%5E%7B-5%7D%20%5C%2C%20mol%20%5C%2C%20L%5E%7B-1%7D$ . The correct option is:

$1.75%20%5Ctimes%2010%5E%7B-5%7D%20%5C%2C%20mol%20%5C%2C%20L%5E%7B-1%7D$

About Conductance - NEET-UG

Conductance is a vital chapter for NEET-UG aspirants. Mastering the concepts covered in this chapter is essential for securing a top rank.

By rigorously practicing the previous year questions associated with this chapter, you can identify high-yield topics, understand the examiner's perspective, and boost your confidence during the actual exam.

Frequently Asked Questions

Why focus on Conductance PYQs?

Analyzing PYQs for this specific chapter reveals the most frequently tested concepts and the typical complexity of questions, allowing you to tailor your study plan efficiently.

How to best use this analysis?

Review the topic breakdown to see which sub-topics within Conductance carry the most weight. Then, tackle the questions iteratively to solidify your understanding.

High-Yield Trend

Chapter Questions
1 MCQs

Official Solution

About Conductance - NEET-UG

Frequently Asked Questions

Why focus on Conductance PYQs?

How to best use this analysis?

Conductance

High-Yield Trend

Chapter Questions 1 MCQs

Official Solution

About Conductance - NEET-UG

Frequently Asked Questions

Why focus on Conductance PYQs?

How to best use this analysis?

Chapter Questions
1 MCQs