Question

On heating a mixture of one mole each of $L{i}_{2}C{O}_3,MgC{O}_3$ and $N{a}_{2}C{O}_3$, the volume of $C{O}_2$ evolved under STP conditions will be:

• A. $67.2L$
• B. $33.6L$
• C. $44.8L$
• D. $22.4L$

Answer 1

Answer: (C)

$44.8L$

$N{a}_{2}C{O}_3$ does not decompose on heating while both $L{i}_{2}C{O}_3$ and $MgC{O}_3$ give $C{O}_2$

$MgC{O}_3\stackrel{△}{\to }MgO+C{O}_2$

$1mole$ $-$ $-$

$-$ $1mole$ $1mole$

$L{i}_2{O}_3\stackrel{△}{\to }L{i}_{2}O+C{O}_2$

$1mole$ $1mole$ $1mole$

Therefore $2$ moles $C{O}_2$ will be evolved. So, volume occupied by $2$ mole gas at STP is

$\Rightarrow 2\times 22.4=44.8liters$