The standard enthalpies of formation of Al2O3 and CaO are $-$1675 kJ mol-1 and $-$635 kJ mol$-$1 respectively.
For the reaction
3CaO + 2Al $\to$ 3Ca + Al2O3 the standard reaction enthalpy $\Delta$rH0 = _________ kJ.
(Round off to the Nearest Integer)
Answer (integer)
230
Solution
$$3CaO + 2Al\mathrel{\mathop{\kern0pt\longrightarrow}
\limits_{}} 3Ca + A{l_2}{O_3}$$<br><br>$$\Delta H_{reaction}^o = 3\Delta {H^o}_f(Ca,s) + \Delta {H^o}_f(A{l_2}{O_3},s) - 3\Delta {H^o}_f(CaO,s) - 2\Delta {H^o}_f(Al,S)$$<br><br>$= 0 + ( - 1675) - 3( - 635) - 0$<br><br>$= - 1675 + 1905$<br><br>$= 230$ KJ
About this question
Subject: Chemistry · Chapter: Thermodynamics · Topic: Zeroth and First Law
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