Ionic Product of Water (Kw)
Understand the concept of Kw, its temperature dependence, and its role in determining the neutrality and pH of water.
Why this shows up in the exam
You may be asked to use Kw in pH calculations or explain its variation with temperature.
How NEET tests this
Practise it
These are real questions from past NEET papers that test this exact idea.
The ionic product of water at 25°C is 10⁻¹⁴. Its ionic product at 90°C will be,
Push further
More challenging3 harder questions built from the past papers above — a step up in difficulty, with distractors designed so you can't get there by elimination. Written and checked by our reviewers, not from a real paper.
At 0°C, the ionic product of water (Kw) is 0.113 × 10⁻¹⁴. What is the pH of a neutral solution at this temperature?
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