Explanation:
Magneisum chlorate will decompose according to the following equation:
Mg(ClO₃)₂ ----> MgCl₂ + 3 O₂
According to coefficients of the reaction, 3 moles of O₂ will be produced when 1 mol of Mg(ClO₃)₂ is decomposed. So the molar ratio between Mg(ClO₃)₂ and O₂ is 1 to 3. We can use this relationship to find the number of moles of O₂ that will be produced from the decomposition of 5.50 moles of Mg(ClO₃)₂.
1 mol of Mg(ClO₃)₂ : 3 moles of O₂ molar ratio
moles of O₂ = 5.50 moles of Mg(ClO₃)₂ * 3 moles of O₂ /(1 mol of Mg(ClO₃)₂)
moles of O₂ = 16.5 moles
Answer: 16.5 moles of oxygen gas will be produced.