Which of the following is the most reactive metal?

Options

A. K
B. Zn
C. Ni
D. Ag

Answer

To determine which of the following metals is the most reactive, we need to analyze their ability to donate electrons, which is a key characteristic of reactivity in metals. The reactivity of metals can be assessed using the electrochemical series, which ranks metals based on their standard reduction potentials (SRP).

### Step-by-Step Solution:

1. **Understanding Reactivity**:
- Reactivity in metals is often associated with their ability to lose electrons and form positive ions. The more readily a metal can donate electrons, the more reactive it is.

2. **Electrochemical Series**:
- The electrochemical series lists metals in order of their standard reduction potentials. Metals with lower (more negative) SRP values are more reactive because they can easily lose electrons.

3. **Identifying the Metals**:
- Let’s consider the metals typically found in the electrochemical series: Lithium (Li), Potassium (K), Barium (Ba), Calcium (Ca), Sodium (Na), and others.

4. **Comparing Standard Reduction Potentials**:
- Lithium (Li) has the highest reactivity among common metals because it has the lowest SRP.
- Potassium (K) and Sodium (Na) are also highly reactive, but Lithium is generally considered the most reactive.

5. **Conclusion**:
- Based on the electrochemical series, Lithium is the most reactive metal among the common metals listed. It can easily donate electrons and is the strongest reducing agent.

### Final Answer:
- **Lithium (Li) is the most reactive metal.**