Question

Sketch a cylinder with ten molecules of helium (He) gas. The cylinder has a movable piston. Label this sketch before. Make an after sketch to represent (a) a decrease in temperature at constant pressure. (b) a decrease in pressure from \(1000 \mathrm{~mm} \mathrm{Hg}\) to \(500 \mathrm{~mm}\) Hg at constant temperature. (c) five molecules of \(\mathrm{H}_{2}\) gas added at constant temperature and pressure.

Short answer

The three scenarios for which 'after' sketches are created are: a) Decrease in temperature at constant pressure b) Decrease in pressure at a constant temperature c) Addition of five molecules of hydrogen gas at constant temperature and pressure

Step-by-step solution

Initial cylinder containing helium (He) gas and movable piston

(Draw a cylinder with 10 helium molecules inside and a movable piston on top. Label this sketch as "Initial cylinder") ### Sketch 2: Decrease temperature at constant pressure ###

Decrease temperature with a constant pressure scenario

(Sketch the cylinder with 10 helium molecules, but with the piston closer to the gas to show a decrease in cylinder volume due to the decrease in temperature at constant pressure. Label this as "Decrease in temperature at constant pressure.") ### Sketch 3: Decrease pressure at constant temperature ###

Decrease pressure at a constant temperature scenario

(Sketch the cylinder with 10 helium molecules, but with the piston raised, or further from the gas, to show an increase in cylinder volume due the decrease in pressure from \(1000 \mathrm{~mm} \mathrm{Hg}\) to \(500 \mathrm{~mm} \mathrm{Hg}\). Label this as "Decrease in pressure at constant temperature.") ### Sketch 4: Adding H₂ gas at constant temperature and pressure ###

Adding H₂ gas at constant temperature and pressure scenario

(Sketch the cylinder with 10 helium and five hydrogen molecules, but maintain the same piston position and overall cylinder volume to demonstrate a constant pressure and temperature. Label the new sketch as "Addition of H₂ gas at constant temperature and pressure.")