99 Percentile Qs Bank for JEE MainChemistrySome Basic Concepts of Chemistry
A 1 g sample of KClO 3 was heated under such conditions that a part of it decomposed according to the equation. (i) 2 KClO 3 ⟶ 2 KCl + 3 O 2 and the remaining underwent change according to the equation (ii) 4 KClO 3 ⟶ 3 KClO 4 + KCl If the amount of O 2 evolved was 146 . 8   mL at NTP , calculate the percentage by weight of KClO 4 in the residue.
Options
- A29 . 3 %
- B49 . 8 %
- C62 . 5 %
- D87 . 1 %
Correct answer
B. 49 . 8 %
Step-by-step solution
Apply POAC on the oxygen atoms in the equation (1) KClO 3 → KCl + O 2 moles of O - atoms in KClO 3 = moles of O - atoms in O 2 since 1 mole of KClO 3 contains 3 moles of O - atoms and 1 mole of O 2 contains 2 moles of O - atoms 3 x moles of KClO 3 = 2 x moles of O 2 3   x wt .   of   KClO 3 mol . wt .   of   KClO 3 = 2   x volume       of   O 2   at   NTP 22400 wt. of   KClO 3 = 2   X   146 . 8   X   122 . 5 3   X