Calculate ?_rH° for the Combustion of Ammonia,
4 NH₃(g) $\ell$

question 8

Multiple Choice

Calculate ?_rH° for the combustion of ammonia,
4 NH₃(g) + 7 O₂(g) ? 4 NO₂(g) + 6 H₂O( $\ell$ )
Using standard molar enthalpies of formation.
$$\begin{array} { l l } \text { molecule } & \Delta _ { f } H ^ { \circ } ( \mathrm { kJ } / \mathrm { mol } - \mathrm { rxn } ) \\\hline \mathrm { NH } _ { 3 } ( \mathrm {~g} ) & - 45.9 \\\mathrm { NO } _ { 2 } ( \mathrm {~g} ) & + 33.1 \\\mathrm { H } _ { 2 } \mathrm { O } ( \ell ) & - 285.8\end{array}$$

• A) +30.24 kJ/mol-rxn
• B) -206.9 kJ/mol-rxn
• C) -298.6 kJ/mol-rxn
• D) -1398.8 kJ/mol-rxn
• E) -1663.6 kJ/mol-rxn

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