Sodium and potassium react with water much more vigorously than lithium because `:`

Options

A. Sodium and potassium have high values of hydration energy as compared to that of lithium.
B. Sodium and potassium have higher melting point than that of lithium.
C. Sodium and potassium have lower melting point than that of lithium.
D. Sodium and potassium have lower hydration energy than that of lithium.

Answer

To solve the question, "Sodium and potassium react with water much more vigorously than lithium because:", we need to analyze the properties of these alkali metals and their behavior when reacting with water.

### Step-by-Step Solution:

1. **Understanding Alkali Metals**:
- Alkali metals include lithium (Li), sodium (Na), and potassium (K). They are found in Group 1 of the periodic table.

2. **Trends in the Periodic Table**:
- As we move down the group from lithium to sodium to potassium, certain properties change. One key property is the melting point.

3. **Melting Point Trend**:
- Lithium has a higher melting point compared to sodium and potassium. This is due to the stronger metallic bonding in lithium because of its smaller atomic size.
- As we go down the group, the atomic size increases, leading to weaker metallic bonds and thus lower melting points for sodium and potassium.

4. **Reactivity with Water**:
- The reactivity of alkali metals with water increases as we move down the group. This is because larger atoms (like sodium and potassium) can lose their outermost electron more easily compared to smaller atoms (like lithium).
- The lower melting point of sodium and potassium means they can melt and react more vigorously with water at room temperature.

5. **Conclusion**:
- Therefore, sodium and potassium react with water much more vigorously than lithium because they have lower melting points and larger atomic sizes, which facilitate easier loss of the outer electron.

### Final Answer:
Sodium and potassium react with water much more vigorously than lithium because they have lower melting points.