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Chemistry

Equilibrium

A Chemistry chapter of the NEET syllabus, and how to practise it for the computer-based exam.

Exam rules change between cycles. Confirm dates, syllabus and pattern against NTA's official site. We are not NTA.

Weightage: what the paper actually did

Equilibrium carried 5 questions in the NEET 2026 paper. One paper is a data point, not a destiny: NTA moves weight between chapters every cycle, which is why the weightage tables deserve care. The stable facts are the paper's shape: 180 questions, 720 marks, +4 right, −1 wrong.

Sample PYQs from this chapter

Real questions NTA asked from Equilibrium, with the answer and the working. Try before you peek.

Question 1 · NEET 2020

Find out the solubility of Ni(OH)₂ in 0.1 M NaOH. Given that the ionic product of Ni(OH)₂ is 2 × 10⁻¹⁵.
  1. A.2 * 10-8 M
  2. B.1 * 10-13 M
  3. C.1 * 108 M
  4. D.2 * 10-13 M
Answer and explanation

Answer: D

The solubility of Ni(OH)2\mathrm{Ni}(\mathrm{OH})_2 in 0.1 M NaOH can be calculated using the solubility product Ksp=2∗10−15K_{sp} = 2 * 10^{-15}. Let s be the solubility of Ni(OH)2\mathrm{Ni}(\mathrm{OH})_2. The concentration of OH−\mathrm{OH}^- from NaOH is 0.1 M, and from Ni(OH)2\mathrm{Ni}(\mathrm{OH})_2 is 2s. Thus, K_{sp} = s * (0.1 + 2s)^2 \(\approx s * (0.1)^2 = 2 * 10^{-15} ⇒ s = 2 * 10^{-13}\ M\). Chapter: Equilibrium.

Question 2 · NEET 2026

In a qualitative analysis, Bi3+\mathrm{Bi}^{3+} is detected by appearance of precipitate of BiO(OH)(s)\mathrm{BiO}(\mathrm{OH})(s). Calculate pH when the following equilibrium exists at 298 K. BiO(OH)(s)⇌BiO+(aq)+OH−(aq)\mathrm{BiO}(\mathrm{OH})(\text{s}) \rightleftharpoons \mathrm{BiO}^{+}(\text{aq}) + \mathrm{OH}^{-}(\text{aq}), K=4×10−10K = 4\times10^{-10}. (Given: log⁡2=0.3010\log 2 = 0.3010)
  1. A.8.714
  2. B.4.699
  3. C.5.286
  4. D.9.301
Answer and explanation

Answer: D

For the dissolution, K=s2K = s^2 since a solid gives equal amounts of BiO+\mathrm{BiO}^{+} and OH−\mathrm{OH}^{-}. So s=4×10−10=2×10−5 M=[OH−]s = \sqrt{4\times10^{-10}} = 2\times10^{-5}\ \text{M} = [\mathrm{OH}^{-}]. Then pOH=5−log⁡2=4.699\text{pOH} = 5 - \log 2 = 4.699 and pH=14−4.699=9.301\text{pH} = 14 - 4.699 = 9.301.

How to practise Equilibrium

Chapter by chapter, against real past-paper questions, on a screen: NEET is computer based from 2027. Read the chapter once, then attempt its PYQs until your accuracy stops climbing, and let the wrong answers tell you which lines to reread. If the chapter keeps refusing to stick, that has its own guide. There is also a free NEET mini mock with answers.

Nearby Chemistry chapters

Questions

How many questions did Equilibrium have in NEET 2026?

Equilibrium carried 5 questions in the NEET 2026 paper. Weightage shifts between cycles, so treat it as a probability, not a promise.

Where can I practise Equilibrium PYQs for NEET?

Explore available chapter-wise NEET practice in BrainIt, free until the 2027 exam. Review explanations and track chapter accuracy to guide your revision. Sample questions from this chapter are on this page.

Is Equilibrium important for NEET 2027?

It is part of the Chemistry syllabus the paper draws from, and NEET 2027 is computer based, so practise it on a screen. Your own accuracy in the chapter matters more than any weightage table: a heavy chapter you already score well on needs less time than a light one you keep missing.

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