Given below are two statements: Statement (I): A buffer solution is the mixture of a salt and an acid or a base mixed…
Ionic Equilibrium · Class 11 · JEE Main Previous Year Question
Given below are two statements:
Statement (I): A buffer solution is the mixture of a salt and an acid or a base mixed in any particular quantities. Statement (II): Blood is a naturally occurring buffer solution whose pH is maintained by concentrations.
Choose the correct option:
- a
Statement I is true but Statement II is false
- b
Both Statement I and Statement II are true
- c✓
Statement I is false but Statement II is true
- d
Both Statement I and Statement II are false
Statement I is false but Statement II is true
Step 1 — Evaluate Statement I: A buffer solution is NOT just any mixture of salt and acid/base. It requires:
- A weak acid and its conjugate base (salt), OR
- A weak base and its conjugate acid (salt)
- Mixed in specific proportions (not "any" quantities)
If equal moles of strong acid and its salt are mixed, it's not a buffer. The statement says "any particular quantities" which is misleading — it must be specific ratios. Statement I is FALSE ✗ (too broad/incorrect)
Step 2 — Evaluate Statement II: Blood pH (7.35–7.45) is maintained by the buffer system: Statement II is TRUE ✓
Answer: Option (3) — Statement I false, Statement II true
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