The order of increasing polarity is `HCI, CO_(2), H_(2)O` and `HF` molecules is

Options

A. `CO_(2), HCI, H_(2)O`
B. `HF, H_(2)O, HCI, CO_(2)`
C. `CO_(2), HF, H_(2)O`
D. `"CC"_(2), HF, H_(2)O, HC`

Explanation

To determine the order of increasing polarity for the molecules HCl, CO₂, H₂O, and HF, we need to analyze the electronegativity differences and molecular shapes of these compounds. Here’s a step-by-step solution:

### Step 1: Understand Polarity
Polarity in a molecule arises from the difference in electronegativity between the atoms involved in a bond. The greater the difference, the more polar the bond. Additionally, the molecular geometry also plays a crucial role in determining the overall polarity of the molecule.

**Hint:** Recall that electronegativity is a measure of an atom's ability to attract electrons in a bond.

### Step 2: Analyze CO₂
CO₂ (carbon dioxide) is a linear molecule. The electronegativity of carbon (C) is approximately 2.5, and that of oxygen (O) is about 3.5. The difference in electronegativity is 1.0. However, because CO₂ is linear, the dipoles cancel each other out, resulting in a non-polar molecule.

**Hint:** Remember that the shape of the molecule can affect the overall dipole moment. Linear molecules with symmetrical charge distribution can be non-polar.

### Step 3: Analyze HCl
HCl (hydrochloric acid) is a polar molecule. The electronegativity of hydrogen (H) is about 2.1, and that of chlorine (Cl) is about 3.0. The difference in electronegativity is 0.9, which indicates that HCl is polar, with a dipole moment directed towards Cl.

**Hint:** Look for the electronegativity values of the atoms involved to determine the polarity of the bond.

### Step 4: Analyze H₂O
H₂O (water) is also a polar molecule. The electronegativity of oxygen (O) is 3.5, and that of hydrogen (H) is 2.1. The difference is 1.4, which indicates a significant polarity. Additionally, the bent shape of the molecule means that the dipole moments do not cancel out, leading to a net dipole moment.

**Hint:** Consider how molecular geometry affects the overall polarity, especially in bent or asymmetrical molecules.

### Step 5: Analyze HF
HF (hydrofluoric acid) is highly polar. The electronegativity of fluorine (F) is about 4.0, while that of hydrogen (H) is 2.1. The difference is 1.9, which is the largest among the molecules considered, indicating that HF has the highest polarity.

**Hint:** The larger the electronegativity difference, the more polar the bond will be.

### Step 6: Order the Molecules by Increasing Polarity
Based on the analysis:
- CO₂ is non-polar.
- HCl is polar but less so than H₂O.
- H₂O is more polar than HCl due to its bent shape and higher electronegativity difference.
- HF is the most polar due to the highest electronegativity difference.

Thus, the order of increasing polarity is:
**CO₂ < HCl < H₂O < HF**

**Final Answer:** CO₂ < HCl < H₂O < HF