Respuesta :
How much potassium chloride, KCl, is produced during the decomposition of 100.0 grams of potassium chlorate, KClO3? 25kg
Answer : The correct answer is : 61.13 g
Potassium chlorate decompose to give potassium chloride and oxygen . The balanced reaction is as follows :
2 KClO₃ → 2 KCl + 3 O₂
Given : Mass of KClO₃ = 100.0 g Mass of KCl = ?
Following are the steps to calculate mass of KCl :
Step 1: Convert mass of KClO₃ to its mole .
[tex] Mole = \frac{Mass}{Molar mass } [/tex]
Molar mass of KClO₃ = 122.55 [tex] \frac{g}{mol} [/tex]
[tex] Mole = \frac{100 g}{ 122.55 \frac{g}{mol}} = \frac{100 g}{122.55 g} * 1 mol [/tex]
Mole = 0.82 mol
Step 2: Find mole ratio between moles of KClO₃ and KCl .
In balanced reaction the coefficients of KClO₃ is 2 and that of KCl is also 2. Hence the mole ratio of KClO₃ : KCl = 2 : 2 = 1 : 1 .
Hence mole of KCl =>
[tex] 0.82 mole of KClO3 * \frac{1 mol KCl}{KClO3} [/tex] = 0.82 mol of KCl .
Step 3: Conversion of mole into grams .
[tex] Mole = \frac{Mass}{Molar mass } [/tex]
Molar mass of KCl = 74.55 [tex] \frac{g}{mol} [/tex]
Plugging value in above formula :
[tex] 0.82 mol KCl = \frac{ mass of KCl }{74.55 \frac{g}{mol}} [/tex]
Multiplying both side by [tex] {74.55 \frac{g}{mol}} [/tex] :
[tex] 0.82 mol KCl * {74.55 \frac{g}{mol} = \frac{ mass of KCl }{74.55 \frac{g}{mol}} * {74.55 \frac{g}{mol} [/tex]
Mass of KCl = 61.13 g
Hence mass of KCl produced = 61.13 g
