- A${0\,^o}C$
- ✓Less than ${0\,^o}C$
- CGreater than ${0\,^o}C$
- DNone of the above
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$C + 2S \to CS_2 ; \,\Delta H_f^o = +117.0\,kJ\,mol^{-1} .......(1)$
$C + O_2 \to CO_2 ; \,\Delta H_f^o = -393\,kJ\,mol^{-1} .......(2)$
$S + O_2 \to SO_2 ; \, \Delta H_f^o = -297\,kJ\,mol^{-1} .......(3)$
The heat of reaction of
$CS_2 + 3O_2 \to CO_2 + 2SO_2$ is
.....$kJ\,mol^{-1}$
Choose the correct statement($s$).
$(A)$ The order of basicity is $II > I > III > IV$ .
$(B)$ The magnitude of $p K_{ b }$ difference between $I$ and $II$ is more than that between $III$ and $IV$.
$(C)$ Resonance effect is more in $III$ than in $IV$.
$(D)$ Steric effect makes compound $IV$ more basic than $III$.
[Given $: h =6.626 \times 10^{-34}\,Js$,Mass of electron $=9.1 \times 10^{-31}$ ]