The number of halogen(s) forming halic (V) acid is __________. — p Block Elements Chemistry Question

💡 Solution & Explanation

**Step 1: Identify what halic (V) acid means** Halic (V) acid refers to oxyacids where the halogen has an oxidation state of +5. The general formula is HXO₃ (where X is the halogen). **Step 2: List all halogens** The halogen group (Group 17) includes: F, Cl, Br, I, and At. **Step 3: Determine which halogens can form +5 oxidation state** - **Fluorine (F)**: Maximum oxidation state is +1 (most electronegative; cannot expand octet effectively) — does NOT form halic(V) acid - **Chlorine (Cl)**: Can achieve +5 oxidation state → forms **chloric acid (HClO₃)** ✓ - **Bromine (Br)**: Can achieve +5 oxidation state → forms **bromic acid (HBrO₃)** ✓ - **Iodine (I)**: Can achieve +5 oxidation state → forms **iodic acid (HIO₃)** ✓ - **Astatine (At)**: Radioactive and unstable; does not form stable halic(V) acid **Step 4: Count the halogens** Only Cl, Br, and I form stable halic(V) acids. Therefore, the answer is **3.00**.