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What is the theoretical yield 115 g of KCl reaction 25 g of oxygen

User BlackMamba
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1 Answer

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Answer:

63.73 g KClO₃

Step-by-step explanation:

We are given the reactants;

  • 115 g of KCl
  • 25 g of oxygen

We are required to determine the theoretical yield;

First we write the equation for the reaction;

2KCl(s) + 3O2(g) → 2KClO3(s)

Second, we determine the number of moles of each reactant;

Moles of KCl = 115 g ÷ 74.55 g/mol

= 1.54 moles

Moles of Oxygen = 25 g ÷ 32.0 g/mol

= 0.78 moles

Thirdly, we determine the rate limiting reagent;

From the equation 2 moles of KCl reacts with 3 moles of O₂

Therefore, 1.54 moles of KCl will require 2.31 moles of O₂, which means KCl is in excess.

Therefore, Oxygen is the rate limiting reagent.

Fourth step: Determine the number of moles of the product KClO₃

From the equation, 3 moles of O₂ reacts to produce 2 moles of KClO₃

Therefore;

Moles of KClO₃ = Moles of O₂ × 2/3

= 0.78 moles × 2/3

= 0.52 moles of KClO₃

Fifth step; Determine the theoretical yield of reaction

Moles of KClO₃ produced = 0.52 moles

But; Mass = Number of moles × molar mass

Therefore;

Mass of KClO₃ = 0.52 moles × 122.55 g/mol

= 63.726 g

= 63.73 g

Therefore, the theoretical yield of the reaction is 63.73 g KClO₃

User Michael Nesterenko
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