A certain salt `(X)` gives the following tests :
(a) Its aqueous solution is alkaline to litmus.
(b) On strong heating, it swells up to give a glassy material `(Y)`.
(c) When conc. `H_(2) SO_(4)` is added to a hot concentrated solution of `(X)`, white crystal of a weak acid `(Z)` separates out.
Identify `(X), (Y) and (Z)` and write down the chemical equations for reaction at steps `a, b` and `c`.

Explanation

To solve the problem step by step, we need to identify the salt (X), the glassy material (Y), and the weak acid (Z) based on the provided tests and write down the corresponding chemical equations.

### Step 1: Identify Salt (X)
- The first test states that the aqueous solution of salt (X) is alkaline to litmus. This indicates that (X) is likely a salt formed from a strong base and a weak acid.
- A common salt that fits this description is **Borax**, which has the chemical formula **Na₂B₄O₇·10H₂O** (sodium tetraborate decahydrate).

### Step 2: Identify Glassy Material (Y)
- The second test mentions that upon strong heating, salt (X) swells up to give a glassy material (Y).
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