The molecule having the largest bond angle is :

Options

A. `H_(2)O`
B. `H_(2)S`
C. `H_(2)Se`
D. `H_(2)Te`

Answer

To determine which molecule has the largest bond angle among H2O, H2S, H2Se, and H2Te, we can analyze the structures and bond angles of these molecules step by step.

### Step 1: Identify the central atom and its hybridization
- The central atom in all these molecules is from Group 16 of the periodic table: Oxygen (O) in H2O, Sulfur (S) in H2S, Selenium (Se) in H2Se, and Tellurium (Te) in H2Te.
- The hybridization of these molecules is determined by the number of bonding pairs and lone pairs on the central atom.

### Step 2: Analyze H2O (Water)
- In H2O, the oxygen atom has two hydrogen atoms bonded to it and two lone pairs of electrons.
- The hybridization is sp³, leading to a bent molecular geometry.
- The bond angle in H2O is approximately 104.5°.

### Step 3: Analyze H2S (Hydrogen Sulfide)
- In H2S, the sulfur atom also has two hydrogen atoms bonded to it and two lone pairs.
- The hybridization is also sp³, resulting in a bent shape.
- However, due to the larger size of sulfur compared to oxygen, the bond angle in H2S is less than that in H2O, approximately 92°.

### Step 4: Analyze H2Se (Hydrogen Selenide)
- In H2Se, the selenium atom has two hydrogen atoms and two lone pairs.
- The hybridization remains sp³, and the shape is bent.
- The bond angle in H2Se is even smaller than in H2S, approximately 88°.

### Step 5: Analyze H2Te (Hydrogen Telluride)
- In H2Te, the tellurium atom has two hydrogen atoms and two lone pairs.
- The hybridization is still sp³, and the shape is bent.
- The bond angle in H2Te is the smallest of all, approximately 82°.

### Step 6: Compare the bond angles
- H2O: 104.5°
- H2S: 92°
- H2Se: 88°
- H2Te: 82°

### Conclusion
The molecule with the largest bond angle is **H2O**.