Question

In an experiment, potassium chlorate decomposed according to the following chemical equation.

Answer 1

Answer:  

(240 × 3 × 31.998)/(122.5 × 2)   g

Step-by-step explanation:

We know we will need a balanced equation with masses and molar masses, so let’s gather all the information in one place.  

M_r:          122.5                31.998

               2KClO₃ ⟶ 2KCl + 3O₂

Mass/g:     240  

Mass of O₂ = 240 g KClO₃ × (1 mol KClO₃/122.5 g KClO₃) × (3 mol O₂/2 mol KClO₃)  × (31.998 g O₂/1 mol O₂) = 94.0 g O₂

Mass of O₂= (240 × 3 × 31.998)/(2 × 122.5) = 94.0 g O₂