Arrange the following in order of property indicated for each set:
`(i) H_(2)O,H_(2)S,H_(2)Se,H_(2)Te` - Increasing acidic character
(ii) `HF,HCl,HBr,HI` - decreasing bond enthalpy

Explanation

To solve the problem, we need to arrange the compounds based on the specified properties. Let's tackle each part step by step.

### Part (i): Increasing Acidic Character of H₂O, H₂S, H₂Se, H₂Te

1. **Identify the Compounds**: We have four compounds: H₂O (water), H₂S (hydrogen sulfide), H₂Se (hydrogen selenide), and H₂Te (hydrogen telluride).

2. **Understand the Trend**: The acidic character of hydrides of group 16 elements increases as we move down the group from oxygen to tellurium. This is because the bond strength decreases and the stability of the conjugate base increases.

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