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Q.
The numbers of moles of $BaCO_3$ which contain $1.5\, moles$ of oxygen atoms is
Some Basic Concepts of Chemistry
Solution:
$\therefore 3$ moles of oxygen is that in $1$ mole of $BaCO_3$
$\therefore 1.5$ moles of oxygen is that in mole of $BaCO_3$
$=\frac{1}{3}\times1.5=\frac{1}{2}=0.5$