Nitric oxide reacts with oxygen according to

CHEMISTRY · Subjective · A Level · Chemistry · Amount of substance · Amount of substance

Problem

2\text{NO}(g)+\text{O}_2(g)\rightarrow 2\text{NO}_2(g)

, for which

\Delta H=-114\,\text{kJ}

per reaction as written. A mixture contains

1.20\,\text{g}

\text{NO}

and

0.80\,\text{g}

\text{O}_2

. After the reaction reaches completion at constant pressure, calculate (i) the heat

q

released (include sign) and (ii) the mass of the excess reactant that remains.