Which of the following is strong base?
Correct answer: A. NaOH
- A. NaOH
- B. H₂O
- C. H₃O⁺
- D. NH₃
Explanation
The correct answer is NaOH. Sodium hydroxide is a strong base because it completely dissociates in water to release hydroxide ions (OH⁻), resulting in a high pH level. H₂O is neutral and does not dissociate to release significant amounts of OH⁻. H₃O⁺ is actually a hydronium ion, which is an indicator of an acidic solution, not basic. NH₃ (Ammonia) is a weak base that only partially dissociates in water, making it less effective than strong bases like NaOH.
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About Acids, Bases and Salts
Acid and base behaviour is explained through the Bronsted-Lowry transfer of protons and the Lewis donation or acceptance of electron pairs. The topic includes pH, pOH, ionisation and water equilibrium, plus salt formation and hydrolysis, where a salt solution may become acidic, basic or neutral.
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