January 2019 NY Regents Chemistry Exam
35 Given the reaction: 2KClO3(s) → 2KCl(s) + 3O2(g) How many moles of KClO3 must completely react to produce 6 moles of O2? (1) 1 mole
(2) 2 moles
(3) 6 moles
(4) 4 moles
Solution:The coefficients in the equation are 3 for O2 and 2 for KClO3. This means 3 moles of O2 will be produced when 2 moles of KClO3 are reacted. Therefore, for 6 moles of O2 which is twice the amount, we would get 2*2= 4moles of KClO3.
Answer:4
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