What is meant by entropy? Predict whether the following changes involve an increases or decreases of entropy:
(i) `Cr^(3+)(aq) + 6H_(2)O(g) to [Cr(H_(2)O_(6))]^(3+(aq))`.
(ii) Sublimation of ammonium chloride.
(iii)Crystallization of salt from brine solution.

Explanation

### Step-by-Step Solution:

**Definition of Entropy:**
1. **Entropy** is a measure of the degree of randomness or disorder in a system. It quantifies how much energy in a system is unavailable to do work and reflects the number of ways a system can be arranged. Higher entropy indicates greater disorder.

**Analyzing the Given Changes:**

**(i) Reaction: `Cr^(3+)(aq) + 6H_(2)O(g) → [Cr(H_(2)O_(6))]^(3+(aq))`**
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