MCQ
The energy is lowest for the orbital :
- ✓$4s$
- B$4p$
- C$3d$
- D$4f$
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$(A)$ $2 CO ( g )+ O _2( g ) \rightarrow 2 CO _2( g ) \quad \Delta H _1^\theta=- x\,kJ\,mol { }^{-1}$
$(B)$ $C$ (graphite) $+ O _2$ (g) $\rightarrow CO _2$ (g) $\Delta H _2^\theta=- y\,kJ\,mol -1$ The $\Delta H ^\theta$ for the reaction $......$.$C ($ graphite $)+\frac{1}{2} O _2( g ) \rightarrow CO ( g )$ is
$(i)$ $\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{C{H_3} - {C^ \mathbf{-} }} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}}
\end{array}$
$(ii)$ $H _{2} C = CH - CH _{2}$
$(iii)$ $HC \equiv \stackrel{\ominus}{ C }$
$(iv)$ $\stackrel{\ominus}{ CH _{3}}$
$(v)$ $\stackrel{\ominus}{{ }_{ CN }}$