The bond angle in water molecule is nearly Or Directed bonds in water forms an angle of

Options

A. `120^@`
B. `180^@`
C. `109^@28'`
D. `104^@ 30'`

Explanation

To determine the bond angle in a water molecule, we can follow these steps:

### Step 1: Understand the Structure of Water
Water (H₂O) consists of one oxygen atom bonded to two hydrogen atoms. The oxygen atom has six valence electrons, two of which are used to form bonds with hydrogen atoms.

**Hint:** Remember that the molecular geometry is influenced by the number of bonds and lone pairs around the central atom.

### Step 2: Identify the Lone Pairs
In the water molecule, after forming bonds with hydrogen, the oxygen atom has four remaining electrons. These four electrons exist as two lone pairs.

**Hint:** Count the number of lone pairs on the central atom to understand how they affect the molecular geometry.

### Step 3: Calculate the Steric Number
The steric number is calculated as the sum of the number of sigma bonds and the number of lone pairs around the central atom. In water, there are:
- 2 sigma bonds (from the two H-O bonds)
- 2 lone pairs

Thus, the steric number = 2 (sigma bonds) + 2 (lone pairs) = 4.

**Hint:** The steric number helps determine the hybridization and the molecular shape.

### Step 4: Determine the Hybridization
With a steric number of 4, the hybridization of the oxygen atom in water is sp³. In an ideal tetrahedral arrangement, the bond angles would be approximately 109.5°.

**Hint:** Recall that hybridization type (sp, sp², sp³) correlates with the steric number.

### Step 5: Adjust for Lone Pair Repulsions
However, the presence of lone pairs affects the bond angles. Lone pairs exert greater repulsive forces than bonding pairs. In water, the two lone pairs push the hydrogen atoms closer together, reducing the bond angle from the ideal tetrahedral angle.

**Hint:** Consider how lone pair-bond pair repulsions can alter the expected bond angles.

### Step 6: Final Bond Angle
Due to the lone pair repulsions, the bond angle in the water molecule is approximately 104.5°.

**Hint:** Remember that the actual bond angle can be less than the ideal angle due to repulsions from lone pairs.

### Conclusion
The bond angle in a water molecule is nearly 104.5°.