Which of the following substances provides hydroxide ions (OH−) when dissolved in water?
Answer and explanation
Correct answer: Sodium hydroxide
According to the aqueous definition of a base, a substance that produces hydroxide ions in water shows basic behaviour. Sodium hydroxide dissociates as NaOH → Na+ + OH−, so option B is correct. Hydrochloric acid produces hydrogen ions, carbon dioxide forms carbonic acid in water, and sodium chloride separates into sodium and chloride ions without directly providing hydroxide ions.
Frequently asked questions
What is the correct answer to this question?
Sodium hydroxide
Why is this the correct answer?
According to the aqueous definition of a base, a substance that produces hydroxide ions in water shows basic behaviour. Sodium hydroxide dissociates as NaOH → Na+ + OH−, so option B is correct. Hydrochloric acid produces hydrogen ions, carbon dioxide forms carbonic acid in water, and sodium chloride separates into sodium and chloride ions without directly providing hydroxide ions.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Acids, Bases, and Salts.
