The calorific value of hydrogen gas is $-143 \ kJ \ g^{-1}$. The standard enthalpy of formation of $H_2O$ will be $—$

  • A
    $-143 \ kJ \ mol^{-1}$
  • B
    $+143 \ kJ \ mol^{-1}$
  • C
    $-286 \ kJ \ mol^{-1}$
  • D
    $+286 \ kJ \ mol^{-1}$

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Similar Questions

Given that,$C_{(s)} + O_{2(g)} \longrightarrow CO_{2(g)} ; \Delta H^{\circ} = -x \ kJ \ mol^{-1}$ and $2CO_{(g)} + O_{2(g)} \longrightarrow 2CO_{2(g)} ; \Delta H^{\circ} = -y \ kJ \ mol^{-1}$. The enthalpy of formation of $CO$ will be:

If the bond energies of $H-H$,$Br-Br$ and $H-Br$ are $433$,$192$ and $364 \ kJ \ mol^{-1}$ respectively,then $\Delta H^{\circ}$ for the reaction: $H_{2(g)} + Br_{2(g)} \rightarrow 2HBr_{(g)}$ is:

If the bond formation energy of the $H-H$ bond is $-433 \ kJ \ mol^{-1}$,find the bond dissociation energy for $0.5 \ mol$ of $H_{2(g)}$. (in $kJ$)

The correct order of $\Delta_{f} H^{\circ}$ values of Diamond $(I)$, Graphite $(II)$, and Fullerene $(III)$ is:

$S_{\text{(rhombic)}} + O_{2(g)} \rightarrow SO_{2(g)}; \Delta H = -297.5 \, kJ$
$S_{\text{(monoclinic)}} + O_{2(g)} \rightarrow SO_{2(g)}; \Delta H = -300 \, kJ$
From the given data,which of the following statements is correct?

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