Chemistry - Complete Pblock- Question with Solution | TestHub
Halogens form a variety of oxides, most of which are unstable : Br₂O, BrO₂, BrO₃, Cl₂O₇, I₂O₅, ClO₂. How many of the following statements about these oxides are CORRECT?
(i) Br₂O, BrO₂ and BrO₃ all exist only at low temperature.
(ii) ClO₂ is an odd-electron, paramagnetic molecule.
(iii) Cl₂O₇ is the anhydride of chloric acid, HClO₃.
(iv) I₂O₅ is a solid oxidising agent used to oxidise CO to CO₂ in gas analysis.
Answer:
Solution:
(i) Correct - all three bromine oxides are unstable and exist only at low temperature. (ii) Correct - ClO₂ has an unpaired electron (odd-electron molecule) and is paramagnetic. (iii) INCORRECT - Cl₂O₇ is the anhydride of PERchloric acid (2HClO₄ − H₂O → Cl₂O₇), not HClO₃. (iv) Correct - I₂O₅ + 5CO → I₂ + 5CO₂ is the standard CO estimation reaction. Count = 3.
