Identify the correct order of acidic strengths -
`CÓ_(2)`, CuO, CaO, `H_(2)O`

Options

A. `CaÓltCuOltH_(2)OltCO_(2)`
B. `H_(2)Olt CuOltCaltCO_(2)`
C. `CaOltH_(2)Olt CuOltCO_(2)`
D. `H_(2)O lt CÓ_(2)lt CaoltCuO`

Answer

To determine the correct order of acidic strengths for the oxides \( \text{CO}_2 \), \( \text{CuO} \), \( \text{CaO} \), and \( \text{H}_2\text{O} \), we can follow these steps:

### Step 1: Identify the nature of the oxides
- **\( \text{CO}_2 \)**: This is a non-metal oxide (oxide of carbon) and is known to be acidic.
- **\( \text{CuO} \)**: This is a metal oxide (oxide of copper) and is generally considered a basic oxide, but it can act as a weak acid in some reactions.
- **\( \text{CaO} \)**: This is also a metal oxide (oxide of calcium) and is strongly basic.
- **\( \text{H}_2\text{O} \)**: Water can act as a neutral substance but has some acidic properties when it reacts with bases.

### Step 2: Analyze the acidic character
- Non-metal oxides tend to be acidic, while metal oxides tend to be basic.
- Among the given oxides, \( \text{CO}_2 \) is the most acidic due to its non-metallic nature.
- \( \text{H}_2\text{O} \) has some acidic properties but is less acidic than \( \text{CO}_2 \).
- \( \text{CuO} \) is a weak base, and \( \text{CaO} \) is a strong base.

### Step 3: Establish the order of acidic strength
Based on the analysis:
1. **Least acidic**: \( \text{CaO} \) (strongly basic)
2. **Next**: \( \text{CuO} \) (weakly basic)
3. **Next**: \( \text{H}_2\text{O} \) (neutral with some acidity)
4. **Most acidic**: \( \text{CO}_2 \) (acidic)

### Final Order of Acidic Strength
Thus, the correct order of acidic strengths from least to most acidic is:
\[ \text{CaO} < \text{CuO} < \text{H}_2\text{O} < \text{CO}_2 \]