1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

# A sample containing only CaCO3 and MgCO3 is ignited to CaO and MgO. The mixture of oxides produced weight exactly half as much as the original sample. The mass percentages of CaCO3 and MgCO3 in the sample are respectively :

A
28.4%, 71.6%
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
71.6%, 28.4%
No worries! Weâ€˜ve got your back. Try BYJUâ€˜S free classes today!
C
56.7%, 43.3%
No worries! Weâ€˜ve got your back. Try BYJUâ€˜S free classes today!
D
78.5%, 21.5%
No worries! Weâ€˜ve got your back. Try BYJUâ€˜S free classes today!
Open in App
Solution

## The correct option is D 28.4%, 71.6%The molar masses of calcium carbonate, magnesium carbonate, calcium oxide and magnesium oxide are 100 g/mol, 84.3 g/mol, 56 g/mol and 40.3 g/mol respectively.Let 100 g of original sample contains x g of calcium carbonate and 100−x g of magnesium carbonate respectively.The amounts of calcium oxide and magnesium oxide obtained on the decomposition will be 0.56x g and 0.478(100−x) g respectively.Hence, x+100−x=2(0.56x+0.478(100−x)).Hence, x=28.4 and 100−x=71.6

Suggest Corrections
0
Join BYJU'S Learning Program
Related Videos
Calcium Hydroxide
CHEMISTRY
Watch in App
Explore more
Join BYJU'S Learning Program