Solid potassium chlorate (KClO 3 ) decomposes into potassium chloride and oxygen
ID: 507783 • Letter: S
Question
Solid potassium chlorate (KClO3) decomposes into potassium chloride and oxygen gas. How many moles of potassium chlorate would need to decompose to supply the minimum amount of oxygen needed to burn 32.0 g of methane?: * A. 4/3 B. 3/2 C. 8/3 D. 32/3 E. 6 Solid potassium chlorate (KClO3) decomposes into potassium chloride and oxygen gas. How many moles of potassium chlorate would need to decompose to supply the minimum amount of oxygen needed to burn 32.0 g of methane?: * A. 4/3 B. 3/2 C. 8/3 D. 32/3 E. 6Explanation / Answer
1st find the mol of O2 required to burn 32.0 g CH4 completely
CH4 + 2O2 —> CO2 + 2H2O
mol of CH4 = mass / molar mass
= 32.0 / 16.0
= 2 mol
according to above reaction,
mol of O2 required = 2*mol of CH4
= 2*2 mol
= 4.0 mol
So, 4.0 mol of O2 must be produced from KClO3
2KClO3 —> 2KCl + 3O2
mol of KClO3 required = (2/3)*mol of O2
= (2/3)*4.0 mol
= 8/3 mol
Answer: C