Which of the following is incorrect statement?

Options

A. LiCl forms hydrated salt LiCl. `2H_(2)O`
B. On heating, `LiNO_(3)` gives `LiNO_(2)` and `O_(2)`
C. Li is the strongest reducing agent
D. Among alkali metals `Li` has the highest melting point.

Answer

To determine which of the statements is incorrect, we will analyze each statement one by one.

### Step 1: Analyze Statement A
**Statement A:** "LiCl forms hydrated salt."

- Lithium chloride (LiCl) is known to form hydrated salts. When dissolved in water, it readily forms LiCl·xH₂O (where x can vary depending on conditions).
- **Conclusion:** This statement is **correct**.

### Step 2: Analyze Statement B
**Statement B:** "On heating LiNO3 gives LiNO2 and O2."

- When lithium nitrate (LiNO₃) is heated, it decomposes to form lithium oxide (Li₂O), nitrogen dioxide (NO₂), and oxygen (O₂). The reaction can be represented as:
\[ 4 \text{LiNO}_3 \rightarrow 2 \text{Li}_2\text{O} + 4 \text{NO}_2 + \text{O}_2 \]
- **Conclusion:** This statement is **incorrect**.

### Step 3: Analyze Statement C
**Statement C:** "Li is the strongest reducing reagent."

- Lithium has a high negative standard reduction potential (approximately -3.05 V for the half-reaction Li⁺ + e⁻ → Li). This indicates that lithium is very willing to lose an electron, making it a strong reducing agent.
- **Conclusion:** This statement is **correct**.

### Step 4: Analyze Statement D
**Statement D:** "Among the alkali metals, lithium has the highest melting point."

- Lithium does indeed have the highest melting point among the alkali metals. This is due to its small atomic size and high ionization energy, which leads to stronger metallic bonding.
- **Conclusion:** This statement is **correct**.

### Final Conclusion
After analyzing all the statements:
- Statement A: Correct
- Statement B: Incorrect
- Statement C: Correct
- Statement D: Correct

Thus, the incorrect statement is **Statement B**.