\(\left.\begin{array}{cc}0.8 g & x \text { cal } \\ 12 g & (?)\end{array}\right\}=\frac{12 x }{0.8}=15 x\)
\(ii)\) \(C +\frac{1}{2} O _2 \rightarrow CO\)
\(\left.\begin{array}{cc}0.8 g & \text { y cal } \\ \therefore 12 g & \text { (?) }\end{array}\right\}=\frac{12 y }{0.8}=15 y\)
\((i) - (ii):\) \(CO +\frac{1}{2} O _2 \longrightarrow CO _2\)
\(\left.\begin{array}{r}28 \,g \rightarrow 15 x -15 y \\ \therefore 1.86\, g \rightarrow(?)\end{array}\right\}=\frac{1.86 \times 15( x - y )}{28}\)
\(=\frac{27.9(x-y)}{28}=x-y\)
$C$ $($હીરા$)$ $ + {O_2}(g) \to C{O_2}(g);\,\Delta H = - 393.5$
જો ગ્રેફાઇટથી હીરો બને તો ઉપરના આંકડા પરથી $\Delta H$.......$kJ$