The variation of pressure with volume of the gas at different temperatures can be graphically represented as shown in Fig. 5.3. On the basis of this graph answer the following questions.
(i) How will the volume of a gas change if its pressure is increased at constant temperature?
(ii) At a constant pressure, how will the volume of a gas change if the temperature is increased from 200K to 400K?
Fig. 5.3.
According to the graph:
(i) As the temperature is constant, and the pressure is increasing the change in the volume is seen as decreasing exponentially.
As we know that when the pressure increases at the constant temperature the volume decreases.
(ii) At the constant pressure, by increasing temperature the volume of gas increases.
(This can easily be seen by graph, by drawing the line parallel to volume axis. When we draw a line parallel to Volume axis, it cuts blue line (200K) as well as the green line(400K), the point at which the line parallel to volume axis cuts the blue and green line, we draw another line perpendicular to Volume axis to get the values of the volume at 200K and 400K.) The yellow line shows the two value of volume at constant pressure.
