A : `ScH_(2)` is an example of ionic hydride.
R : All metal forms ionic hydride.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1)
B. If both Assertion & Reason are true but the reason is not the correct explanantion of the assertion, then mark (2)
C. If assertion is true statements but Reason is false, then mark (3)
D. If both Assertion and Reason are false statements, then mark (4)

Answer

To solve the question, we need to analyze both the assertion (A) and the reason (R) provided:

**Assertion (A):** `ScH_(2)` is an example of ionic hydride.
**Reason (R):** All metals form ionic hydrides.

### Step-by-step Solution:

1. **Understanding Ionic Hydrides:**
- Ionic hydrides are typically formed by alkali and alkaline earth metals (Group 1 and Group 2 elements) which have a strong tendency to lose electrons and form positive ions (cations). These metals react with hydrogen to form ionic compounds.

2. **Analyzing the Assertion:**
- The assertion states that `ScH_(2)` (scandium hydride) is an example of ionic hydride. Scandium (Sc) is a transition metal (located in the d-block of the periodic table).
- Transition metals generally form metallic hydrides, which are characterized by covalent bonding rather than ionic bonding. Therefore, the assertion that `ScH_(2)` is an ionic hydride is incorrect.

3. **Analyzing the Reason:**
- The reason states that all metals form ionic hydrides. This is not true because while alkali and alkaline earth metals do form ionic hydrides, many transition metals (like scandium) form metallic hydrides with covalent character.
- Therefore, the reason is also incorrect.

4. **Conclusion:**
- Since both the assertion and the reason are incorrect, we conclude that the correct answer is that both the assertion and the reason are false.

### Final Answer:
Both assertion and reason are false.

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