Top Chemical Equilibrium Questions for NEET

Chemical equilibrium is one of the most scoring and concept-driven chapters in NEET Chemistry. Every year, multiple questions are directly asked from equilibrium constants, Le Chatelier’s principle, and ionic equilibrium. If you prepare the Top 5 Chemical Equilibrium Questions, you can easily secure those marks with accuracy and confidence.

In this article, we will go through the Top 5 Chemical Equilibrium Questions that are frequently repeated in NEET PYQs, along with clear explanations and solving strategies. Understanding these problems will strengthen your conceptual clarity and improve your problem-solving speed.

Question 1: Relation Between Kp and Kc

For a gaseous reaction:$$N_2(g) + 3H_2(g) \rightleftharpoons 2NH_3(g)$$N2​(g)+3H2​(g)⇌2NH3​(g)

Find the relation between $K_p$Kp​ and $K_c$Kc​.

Solution

The relation between equilibrium constants is:$$K_p = K_c (RT)^{\Delta n}$$Kp​=Kc​(RT)Δn

Where:

• $\Delta n = \text{moles of gaseous products} – \text{moles of gaseous reactants}$Δn=moles of gaseous products−moles of gaseous reactants

Here:$$\Delta n = 2 – (1 + 3) = -2$$Δn=2−(1+3)=−2

So,$$K_p = K_c (RT)^{-2}$$Kp​=Kc​(RT)−2

Final Answer:

$$K_p = \frac{K_c}{(RT)^2}$$Kp​=(RT)2Kc​​

This is one of the most important problems in the Top 5 Chemical Equilibrium Questions, as NEET frequently tests this concept.

Question 2: Le Chatelier’s Principle Application

What happens to equilibrium when pressure is increased for the reaction:$$2SO_2(g) + O_2(g) \rightleftharpoons 2SO_3(g)$$2SO2​(g)+O2​(g)⇌2SO3​(g)

Solution

According to Le Chatelier’s principle:

• Increase in pressure favors the side with fewer moles of gas.

Reactants: 3 moles
Products: 2 moles

So equilibrium shifts towards products.

Final Answer:

Equilibrium shifts to the right, increasing $SO_3$SO3​ formation.

This concept appears repeatedly in the Top 5 Chemical Equilibrium Questions, especially in conceptual MCQs.

Question 3: Degree of Dissociation

For a weak electrolyte, the degree of dissociation $\alpha$α is related to equilibrium constant $K$K and concentration $C$C as:$$K = \frac{C\alpha^2}{1 – \alpha}$$K=1−αCα2​

If $\alpha$α is very small, simplify the expression.

Solution

Since $\alpha \ll 1$α≪1, we approximate:$$1 – \alpha \approx 1$$1−α≈1

Thus:$$K = C\alpha^2$$K=Cα2 $$\alpha = \sqrt{\frac{K}{C}}$$α=CK​​

Final Answer:

$$\alpha = \sqrt{\frac{K}{C}}$$α=CK​​

This formula is a must-remember shortcut from the Top 5 Chemical Equilibrium Questions.

Question 4: Ionic Equilibrium – pH Calculation

Calculate the pH of a 0.01 M HCl solution.

Solution

HCl is a strong acid, so it dissociates completely:$$[H^+] = 0.01 = 10^{-2}$$[H+]=0.01=10−2 $$pH = -\log[H^+]$$pH=−log[H+] $$pH = -\log(10^{-2}) = 2$$pH=−log(10−2)=2

Final Answer:

pH = 2

Direct pH-based questions are very common in the Top 5 Chemical Equilibrium Questions, especially from strong acids and bases.

Question 5: Common Ion Effect

What happens when ammonium chloride (NH₄Cl) is added to ammonium hydroxide (NH₄OH)?

Solution

NH₄OH ⇌ NH₄⁺ + OH⁻

Adding NH₄Cl increases NH₄⁺ concentration.

According to Le Chatelier’s principle:

• Increase in product shifts equilibrium to the left.

Thus:

• Ionization of NH₄OH decreases.

Final Answer:

Ionization decreases due to the common ion effect.

This is a classic conceptual problem included in the Top 5 Chemical Equilibrium Questions every year.

Why These Top 5 Chemical Equilibrium Questions Matter for NEET

The Top 5 Chemical Equilibrium Questions covered here are not random—they represent the exact pattern followed in NEET. Questions are usually:

• Concept-based rather than lengthy
• Formula-driven with small calculations
• Focused on equilibrium shifts, constants, and pH

If you master these Top 5 Chemical Equilibrium Questions, you can confidently attempt most equilibrium problems in the exam.

Preparation Tips for Chemical Equilibrium

To fully utilize the Top 5 Chemical Equilibrium Questions, keep these strategies in mind:

Focus on formulas like $K_p = K_c (RT)^{\Delta n}$Kp​=Kc​(RT)Δn and pH calculations. Practice approximation methods such as $1 – \alpha \approx 1$1−α≈1. Understand Le Chatelier’s principle deeply rather than memorizing it. Pay special attention to ionic equilibrium, especially pH, pOH, and buffer solutions.

Repeated revision of these Top 5 Chemical Equilibrium Questions will help you build speed and accuracy.

FAQs on Top 5 Chemical Equilibrium Questions

What is the weightage of equilibrium in NEET?

Chemical equilibrium usually carries 2–3 questions in NEET, making it a high-weightage chapter.

Are numerical questions difficult in equilibrium?

No, most numerical problems are formula-based and can be solved quickly if concepts are clear.

Is ionic equilibrium important for NEET?

Yes, ionic equilibrium is extremely important and often asked in the form of pH calculations and buffer problems.

How to revise Top 5 Chemical Equilibrium Questions effectively?

Revise formulas daily, solve PYQs multiple times, and focus on conceptual clarity.

Conclusion

The Top 5 Chemical Equilibrium Questions discussed in this article cover the most repeated and high-yield concepts for NEET. By practicing these questions regularly, you can strengthen your fundamentals and improve your score significantly.

Make sure to revise these Top 5 Chemical Equilibrium Questions multiple times before the exam, as they form the backbone of equilibrium-related problems in NEET.