Arrange according to increasing Lewis acid character,
`BF_(3)`, `BCl_(3)`, `BBr_(3)` `BI_(3)`

Explanation

To determine the increasing Lewis acid character of the boron halides \(BF_3\), \(BCl_3\), \(BBr_3\), and \(BI_3\), we need to analyze the ability of each compound to accept electrons. The Lewis acid character is influenced by the ability of the central atom (boron in this case) to accept electron pairs, which is affected by the backbonding from the halogen atoms.

### Step-by-Step Solution:

1. **Understand Lewis Acids**: Lewis acids are defined as species that can accept an electron pair. In this case, boron halides can act as Lewis acids because boron has an incomplete octet and can accept electrons.

2. **Identify the Halogens**: The halogens involved are fluorine (F), chlorine (Cl), bromine (Br), and iodine (I). As we move down the group in the periodic table, the size of the halogen atoms increases, which affects their ability to participate in backbonding with boron.

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