Boron compouns act as Lewis acid because of their `"………….."` nature.

Answer

To answer the question "Boron compounds act as Lewis acid because of their __________ nature," we can follow these steps:

### Step 1: Understand the Definition of Lewis Acids
A Lewis acid is defined as a substance that can accept an electron pair from another species. This means that Lewis acids are electron pair acceptors.

**Hint:** Recall the definition of Lewis acids and their role in chemical reactions.

### Step 2: Analyze Boron Compounds
Boron compounds, such as boron trifluoride (BF3), have a unique electronic structure. Boron typically has three valence electrons and can form three covalent bonds. However, this leaves boron with an incomplete octet, making it electron deficient.

**Hint:** Consider the electronic configuration and bonding of boron to understand its electron deficiency.

### Step 3: Relate Electron Deficiency to Lewis Acidity
Because boron compounds are electron deficient, they have a tendency to seek out electrons. This characteristic makes them capable of accepting electron pairs from other molecules, thus behaving as Lewis acids.

**Hint:** Think about how electron deficiency influences the behavior of a compound in terms of electron acceptance.

### Step 4: Conclude the Answer
Therefore, we can conclude that boron compounds act as Lewis acids because of their **electron deficient** nature.

**Final Answer:** Boron compounds act as Lewis acids because of their **electron deficient** nature.

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