What of the following anions are present in clay ?

Options

A. `Al_2O_3`
B. `CO`
C. `CO_2`
D. `CaO`

Explanation

To determine which anions are present in clay, we can follow these steps:

### Step 1: Understand the Composition of Clay
Clay is primarily composed of silicate minerals, which typically include various anions. The most common anions found in clay minerals are silicate (SiO4^4−) and aluminum (AlO2^−).

### Step 2: Analyze the Given Options
The question provides several options for anions. We need to evaluate each option to see if it is commonly found in clay.

### Step 3: Identify the Relevant Anions
- **Silicate (SiO4^4−)**: A major component of clay.
- **Aluminate (AlO2^−)**: Also commonly found in clay.
- **Carbonate (CO3^2−)**: While not a primary component, it can be present in some clays.
- **Sulfate (SO4^2−)**: Generally not a major component of clay.

### Step 4: Conclusion
Based on the analysis, the most relevant anions present in clay are silicate and aluminate. If the options included these, they would be the correct answers. However, if CO2 was mentioned in the context of anions, it is important to clarify that CO2 itself is not an anion but can form carbonate ions in solution.

### Final Answer
The correct anion that is commonly associated with clay is **silicate (SiO4^4−)**, and if carbonate (CO3^2−) was an option, it could also be considered.

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