Question

How many grams of KCl is produced if 32.4 grams of O2 is produced?

2KClO3(s) --> 2KCl(s) + 3O2(g)

Question 2 options:

0.54 grams KCl


6.87 grams KCl


25.7 grams KCl


50.3 grams KCl

Answer 1

okay so, the molar mass (Mr) of O2 is 32g

moles = mass/Mr
moleS= 32.4/32= 1.0125mol
the Mr of KCl is 39.1+35.5= 74.6g

the ratio of moles of KCl to O2 is 2 : 3
therefore moles of KCl is (1.0125/3)×2= 0.675mols

mass =moles×Mr=0.675×74.6= 50.355g
rounds up to 50.3g therefore last answer is correct