Which of the following equations has Delta_{f | vedclass

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(A) The standard enthalpy of formation,$\Delta_{f} H^{\circ}$,is defined as the enthalpy change when $1 	ext{ mole}$ of a compound is formed from its

Vedclass · Accepted Answer

$H_{2(g)} + \frac{1}{2} O_{2(g)} \longrightarrow H_{2}O_{(l)}$

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(A) The standard enthalpy of formation,$\Delta_{f} H^{\circ}$,is defined as the enthalpy change when $1 	ext{ mole}$ of a compound is formed from its constituent elements in their standard states.For $\Delta_{f} H^{\circ} = \Delta H^{\circ}$,the reaction must form exactly $1 	ext{ mole}$ of the product from its elements in their standard states.In option $A$,$H_{2(g)} + \frac{1}{2} O_{2(g)} \longrightarrow H_{2}O_{(l)}$ represents the formation of $1 	ext{ mole}$ of liquid water from its elements $H_2$ and $O_2$ in their standard states,thus $\Delta_{f} H^{\circ} = \Delta H^{\circ}$.

Which of the following equations has $\Delta_{f} H^{\circ}$ and $\Delta H^{\circ}$ the same?

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