d
\(C ( S )+ O _{2}( g ) \rightarrow CO _{2}( g )+400\; kJ\)

\(1\; g \;mole\)

\(C ( s )+\frac{1}{2} O _{2}( g ) \rightarrow CO ( g )+100\; kJ \ldots (II)\)

\(0.6 \times 1000\)

\(=600 \;gm\)

\(600 \times \frac{60}{100}\) (Pure Carbon)

\(=360 \;gm =\frac{360}{12}=30 \;mole\) (Pure Carbon)

Carbon converted into \(CO _{2}=\left(30-30 \times \frac{60}{100}\right)\)

\(=12\; mole\)

and carbon converted in \(CO =30 \times \frac{60}{100}=18\; mole\)

Energy generated during \(II\) equation

\(=18 \times 100\)

\(=1800 \;kJ\)

Energy generated during \(I^{st}\) equation

\(=12 \times 400\)

\(=4800\)

Total \(=1800+4800=6600\; kJ\)