Following elements are present in the second period of the periodic table from left to right.
`Li, Be, B, C, N, O, F, Ne`
Few statements are given about these elements :
(i) `O` and `F` exist as monatomic gases.
(ii) `Li` is the lightest element in the period.
(iii) `B` is a metalloid while `C` is a metal.
(iv) `Li` and `F` react to form a compound `LiF`.
The correct statements are

Options

A. (i) and (iii) only
B. (ii) and (iv) only
C. (ii) and (iii) only
D. (i) and (iv) only

Explanation

To determine which statements about the elements in the second period of the periodic table are correct, let's analyze each statement one by one.

### Step 1: Analyze Statement (i)
**Statement:** O and F exist as monatomic gases.

**Analysis:**
- Oxygen (O) exists as O₂ (diatomic gas) and Fluorine (F) exists as F₂ (diatomic gas).
- Therefore, this statement is **incorrect**.

### Step 2: Analyze Statement (ii)
**Statement:** Li is the lightest element in the period.

**Analysis:**
- Lithium (Li) has an atomic mass of approximately 7, which is lower than that of Beryllium (Be), Boron (B), Carbon (C), Nitrogen (N), Oxygen (O), Fluorine (F), and Neon (Ne).
- Therefore, this statement is **correct**.

### Step 3: Analyze Statement (iii)
**Statement:** B is a metalloid while C is a metal.

**Analysis:**
- Boron (B) is indeed classified as a metalloid, but Carbon (C) is a non-metal, not a metal.
- Therefore, this statement is **incorrect**.

### Step 4: Analyze Statement (iv)
**Statement:** Li and F react to form a compound LiF.

**Analysis:**
- Lithium (Li) reacts with Fluorine (F) to form Lithium Fluoride (LiF), which is an ionic compound.
- Therefore, this statement is **correct**.

### Conclusion
Based on the analysis:
- Correct statements are:
- (ii) Li is the lightest element in the period.
- (iv) Li and F react to form a compound LiF.

Thus, the correct statements are (ii) and (iv).

### Final Answer
The correct statements are: (ii) and (iv).

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