Q3 of 18 Page 210

In calcium carbonate, the masses of calcium, carbon and oxygen are in the ratio 10: 3: 12. When 150 grams of a compound was analysed, it was found to contain 60 grams of calcium, 20 grams of carbon and 70 grams of oxygen. Is it calcium carbonate?

Given:


Ratio of masses of calcium, carbon and oxygen in calcium carbonate is 10: 3: 12


Now,


In 150 grams, 60 gram of calcium, 20gram of carbon and 70gram of oxygen


Ratio of masses in 150gram of a compound


⇒ 60: 20: 70


⇒ 6: 2: 7


As we observe that ratio given for calcium carbonate is 10: 3: 12 but in 150 grams of compound the ratio is 6: 2: 7.


∴ 150gram compound is not the calcium carbonate.


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