Which of the following is a salt of 'ous' acid?

Options

A. `Na_2SO_4`
B. `NaNO_3^(+)`
C. `NaClO_2`
D. `NaClO_4`

Explanation

To determine which of the given options is a salt of an 'ous' acid, we need to identify the acids from which these salts are derived. 'Ous' acids typically refer to acids that contain a lower oxidation state of the central atom compared to their 'ic' counterparts.

Let's analyze the given salts one by one:

1. **Na2SO4**:
- This salt is derived from the reaction of sodium hydroxide (NaOH) and sulfuric acid (H2SO4).
- H2SO4 is sulfuric acid, which is an 'ic' acid, not an 'ous' acid.
- Therefore, Na2SO4 is not a salt of an 'ous' acid.

2. **NaNO3**:
- This salt is formed from sodium hydroxide (NaOH) and nitric acid (HNO3).
- HNO3 is nitric acid, which is also an 'ic' acid, not an 'ous' acid.
- Hence, NaNO3 is not a salt of an 'ous' acid.

3. **NaClO2**:
- This salt is produced from sodium hydroxide (NaOH) and chlorous acid (HClO2).
- HClO2 is chlorous acid, which is an 'ous' acid.
- Therefore, NaClO2 is indeed a salt of an 'ous' acid.

4. **NaClO4**:
- This salt comes from the reaction of sodium hydroxide (NaOH) and perchloric acid (HClO4).
- HClO4 is perchloric acid, which is an 'ic' acid, not an 'ous' acid.
- Thus, NaClO4 is not a salt of an 'ous' acid.

Based on the analysis, the only salt that is derived from an 'ous' acid is **NaClO2**.

**Final Answer**: NaClO2 is a salt of an 'ous' acid.