in an experiment, a student wants to increase the rate of a reaction that involves gases. which change to…

in an experiment, a student wants to increase the rate of a reaction that involves gases. which change to the reactants would accomplish this?\nincrease the volume to decrease pressure and to increase concentration.\nincrease the volume to increase pressure and to decrease concentration.\ndecrease the volume to decrease pressure and to increase concentration.\ndecrease the volume to increase pressure and to increase concentration.

in an experiment, a student wants to increase the rate of a reaction that involves gases. which change to the reactants would accomplish this?\nincrease the volume to decrease pressure and to increase concentration.\nincrease the volume to increase pressure and to decrease concentration.\ndecrease the volume to decrease pressure and to increase concentration.\ndecrease the volume to increase pressure and to increase concentration.

Answer

Explanation:

Step1: Recall gas - reaction rate factors

The rate of a gas - phase reaction is affected by concentration and pressure. According to the ideal gas law $PV = nRT$, when the number of moles ($n$) and temperature ($T$) are constant, pressure ($P$) and volume ($V$) are inversely related ($P=\frac{nRT}{V}$), and concentration ($c=\frac{n}{V}$).

Step2: Analyze volume - pressure - concentration relationships

Decreasing the volume of a gas system will increase the pressure (since $P\propto\frac{1}{V}$) and also increase the concentration (since $c\propto\frac{1}{V}$). Higher concentration and higher pressure generally increase the rate of a gas - phase reaction as there are more frequent collisions between reactant molecules.

Answer:

Decrease the volume to increase pressure and to increase concentration.