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Question
Solve the following problem:
What weight of calcium oxide will be formed on heating 19.3 g of calcium carbonate?
(At. wt.: Ca = 40; C = 12; O = 16)
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Solution
Given: Mass of CaCO3 consumed in reaction = 19.3 g
To find: Mass of CaO formed
Calculation: Calcium carbonate decomposes according to the balanced equation,
\[\ce{\underset{\text{40+12+3×16=100 parts}}{CaCO3}->[\Delta]\underset{\text{40+16=56 parts}}{CaO} + \underset{\text{12+2×16=44 parts}}{CO2} ^}\]
So, 100 g of CaCO3 produce 56 g of CaO.
∴ 19.3 g of CaCO3 will produce = `(56"g")/(100 "g")xx19.3 "g"`
= 10.81 g of CaO
Mass of CaO formed = 10.81 g
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