Question

Study the following table and select the correct option:

• A. NaCl from HCl (strong acid) and NaOH (strong base) → Neutral, not basic
• B. Na$_2$CO$_3$ from weak acid (H$_2$CO$_3$) and strong base → Basic, not
• C. Na$_2$SO$_4$ from strong acid and strong base → Neutral, not acidic
• D. CH$_3$COONa from weak acid (CH$_3$COOH) and strong base (NaOH) → Basic

Hint:

Weak acid + Strong base → Basic salt (e.g., CH$_3$COONa).

Answer 1

The Correct Option is D

To determine the nature of salts obtained from acids and bases, it is important to understand the origins of the component ions. The acidity, basicity, or neutrality of the salt depends on whether its constituent acid and base are strong or weak. Let's evaluate each option:

1. NaCl from HCl (strong acid) and NaOH (strong base) → Neutral: Salts formed from a strong acid and a strong base are typically neutral. Therefore, NaCl is neutral as it is formed from HCl and NaOH. This supports the statement given.
2. Na₂CO₃ from weak acid (H₂CO₃) and strong base → Basic: Carbonate salts formed from a weak acid (carbonic acid, H₂CO₃) and a strong base (like NaOH) are generally basic in nature. Thus, Na₂CO₃ is correctly considered basic.
3. Na₂SO₄ from strong acid and strong base → Neutral: When a strong acid such as H₂SO₄ reacts with a strong base such as NaOH, the resultant salt is neutral. Therefore, Na₂SO₄ is neutral, aligning with the statement.
4. CH₃COONa from weak acid (CH₃COOH) and strong base (NaOH) → Basic: Salts formed from weak acids and strong bases, such as sodium acetate (CH₃COONa), are typically basic. This makes the statement correct and is the reason it is the correct answer.

The correct option is the explanation which characterizes sodium acetate (CH₃COONa) as a basic salt, due to it being formed from a weak acid (acetic acid) and a strong base (sodium hydroxide).