A metal in a compound can be a by another metal in the uncombined state here A refers to

Options

A. added
B. decomposed
C. eliminated
D. displaced

Answer

To solve the question regarding the displacement of a metal in a compound by another metal in the uncombined state, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Concept of Displacement Reactions**:
- In chemistry, a displacement reaction occurs when a more reactive metal displaces a less reactive metal from its compound. This is based on the reactivity series of metals.

2. **Identifying the Metals**:
- In the given scenario, we have a metal in a compound (let's denote it as Metal A) and another metal in the uncombined state (denote it as Metal B).

3. **Selecting an Example**:
- Let's consider the example of zinc sulfate (ZnSO₄), where zinc (Zn) is the metal in the compound.

4. **Comparing Reactivity**:
- Now, we need to check if there is a more reactive metal that can displace zinc from zinc sulfate. Aluminum (Al) is a common example of a more reactive metal compared to zinc.

5. **Writing the Displacement Reaction**:
- The displacement reaction can be written as:
\[ 3 \text{ZnSO}_4 + 2 \text{Al} \rightarrow 3 \text{Al}_2(\text{SO}_4)_3 + 3 \text{Zn} \]
- Here, aluminum displaces zinc from zinc sulfate, forming aluminum sulfate and releasing zinc.

6. **Conclusion**:
- Therefore, in this context, the metal in the compound (zinc) can be displaced by another metal (aluminum) in the uncombined state. Thus, the answer to the question is that "E" refers to the metal in the compound which can be displaced.

### Final Answer:
E refers to the metal in a compound (e.g., zinc in zinc sulfate) that can be displaced by a more reactive metal (e.g., aluminum in the uncombined state).

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