PhysicsLAB: Ideal Gases

A gas is confined to a cylindrical container having a movable, yet "snuggly-fitting," lid that slides up and down to accommodate changes in pressure and volume. The diagram shown below, outlines the steps in a heat cycle starting at position A and moving through positions B, C, D and then back to A.

The y-axis is pressure measured in atmospheres (1 atm = 1.01 x 10⁵ Pa) and the x-axis is volume measured in multiples of 10^-2 m³.

If the temperature at point A is 50 ºC, what is the temperature at point B?

In general as you move along a horizontal path away from the y-axis (A → B), called an isobaric expansion, does the temperature of the gas increase or decrease?

increasedecrease

What is the temperature of the confined gas at point C?

If the surface area of the lid of the container is 0.2 m² (it has a radius of 25 cm) then what is the magnitude of the force exerted against the lid by the gas molecules while the gas is at position C?

What is the temperature of the confined gas at point D?

How does the force exerted on the lid of the container by the gas molecules compare at points D and C?

F_C > F_DF_C = F_DF_C < F_D

In general as you move along a vertical path away from the x-axis (D → A), called an isovolumetric process, does the temperature of the gas increase or decrease?

increasedecrease

How many moles of gas are present in the sample?

How many gas molecules are present in the sample?

If the gas present in the sample is nitrogen, then what mass of nitrogen is in the container?

What is the mass of a single nitrogen molecule,

What is the average translational KE of a nitrogen molecule when the gas is at point B?

What is the average speed of one nitrogen molecule in the gas sample when the gas is at point B?

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