Question

Potassium Chlorate decomposes into potassium chloride and oxygen gas. How many grams of oxygen are produced when 8.49 grams of potassium chlorate decompose completely?

Answer 1

3.325 grams

Explanations:

The balanced chemical reaction for the decomposition of potassium chlorate is expressed as:

`2KClO_3\rightarrow2KCl+3O_2`

Determine the mole of potassium chlorate

`\begin{gathered} mole\text{ of KClO}_3=(8.49)/(122.55) \\ mole\text{ of KClO}_3=0.0693mole \end{gathered}`

According to stoichiometry, 2 moles of potassium chlorate produces 3 moles of oxygen. The mole of oxygen required is expressed as:

`\begin{gathered} mole\text{ of O}_2=0.0693moles*(3)/(2) \\ mole\text{ of O}_2=0.1039mole \end{gathered}`

Calculate the required mass of oxygen

`\begin{gathered} Mass\text{ of O}_2=mole* molar\text{ mass} \\ Mass\text{ of O}_2=0.1039*32 \\ Mass\text{ of O}_2=3.325grams \end{gathered}`

Hence the required mass of oxyeen required is 3.325 grams