From the following reaction sequence
Cl2 + 2KOH → KCl + KClO + H2O
3KClO → 2KCl + KClO3
4KClO3 → 3KClO4+KCl
Calculate the mass of chlorine needed to produce 23g of KClO4
142g
The given reactions involve certain compounds which are not needed for calculations.
∴ Balance the reaction in a way that the unnecessary compounds get cancelled.
12Cl2 + 24KOH → 12KClO + 12KCl + 12H2O
12KClO → 8KCl + 4KClO3
4KCIO3→ 3KClO4 + KCl
12Cl2 + 24KOH → 3KClO4+ 21KCl + 12H2O
We cancel the compounds on either side of the arrow
From this final balanced equation
12 moles of Cl2 gives 3 moles of KClO4
12 × (35.5 × 2=71)g = 3 × (138.5)g
∴ 23g of KCIO4=23×12×713×138.5
23g of KClO4 gives≈142g of Cl2
Note: approximate weight of KClO4≈=138