Which of the following is a set of neutral oxides?

Analysis of the Question

The question asks you to identify a group of oxides that are neutral. In chemistry, a neutral oxide is one that does not react with either acids or bases to form salts. Unlike acidic oxides (which react with bases) or basic oxides (which react with acids), neutral oxides remain unchanged in the presence of these substances.

Concept Explanation

To solve this, we need to categorize the common oxides:

1. Neutral Oxides: These are rare. The most common ones you must memorize for JAMB are Carbon(II) oxide (CO), Nitrogen(I) oxide (N$_2$O), and Water (H$_2$O). Nitrogen(II) oxide (NO) is also generally considered neutral.
2. Acidic Oxides: These are usually non-metal oxides like SO$_2$, SO$_3$, CO$_2$, and P$_4$O$_{10}$.
3. Basic Oxides: These are usually metal oxides like Na$_2$O, CaO, and MgO.
4. Amphoteric Oxides: These react with both acids and bases. A classic example is Zinc oxide (ZnO).

Step-by-Step Evaluation

Let's examine the options provided:

• Option A: N$_2$O, H$_2$O, CO • N$_2$O (Nitrous oxide) is neutral. • H$_2$O (Water) is neutral. • CO (Carbon monoxide) is neutral. • This set consists entirely of neutral oxides.

• Option B: N$_2$O, SO$_2$, CO • SO$_2$ is an acidic oxide (it reacts with water to form sulfurous acid). This makes the set incorrect.

• Option C: N$_2$O, Na$_2$O, ZnO • Na$_2$O is a basic oxide. • ZnO is an amphoteric oxide. This makes the set incorrect.

• Option D: N$_2$O, SO$_3$, NO • SO$_3$ is a strongly acidic oxide (it reacts with water to form sulfuric acid). This makes the set incorrect.

Conclusion

Based on the classification of oxides, Option A is the only set where every compound is a neutral oxide.

Exam Tip

When you see a question about oxides, remember the acronym "CAN" for neutral oxides: CO, Aqua (H$_2$O), and Nitrogen oxides (N$_2$O and NO). If you see any other oxides in the list, check if they are metal oxides (usually basic) or non-metal oxides (usually acidic) to quickly eliminate the wrong options!