Ammonia, \(\mathrm{NH}_{3}(g)\), and hydrogen chloride, \(\mathrm{HCl}(g)\), react
to form solid ammonium chloride, \(\mathrm{NH}_{4} \mathrm{Cl}(s)\) :
$$
\mathrm{NH}_{3}(g)+\mathrm{HCl}(g) \longrightarrow \mathrm{NH}_{4}
\mathrm{Cl}(s)
$$
Two 2.00-L flasks at \(25^{\circ} \mathrm{C}\) are connected by a stopcock, as
shown in the drawing. One flask contains \(5.00 \mathrm{~g}\)
\(\mathrm{NH}_{3}(g)\), and the other contains \(5.00 \mathrm{~g} \mathrm{HCl}(g)
.\) When the stopcock is opened, the gases react until one is completely
consumed. (a) Which gas will remain in the system after the reaction is
complete? (b) What will be the final pressure of the system after the reaction
is complete? (Neglect the volume of the ammonium chloride formed.)