A chemistry class conducts an investigation in which the pressure of of neon gas…
CHEMISTRY · Multi-part · A Level · Chemistry · Amount of substance · Amount of substance
Problem
A chemistry class conducts an investigation in which the pressure of 0.0400mol of neon gas confined to a fixed volume of 1.00L is measured at several temperatures. The data are shown in the table below.
Temperature T (K): 270, 290, 310, 330, 350
Pressure P (kPa): 90.1, 97.1, 104.2, 111.4, 118.4
Assume that uncertainties in the pressure readings are ±0.5kPa and uncertainties in the temperature readings are ±1K. Neon behaves ideally over this range.
(1) Describe how you would construct a best-fit straight line for a graph of pressure versus temperature using the data provided. Then determine the numerical value of the slope of that line in SI units.
(2) Use the slope you obtained to calculate an experimental value for the universal gas constant R. Show all unit conversions clearly.
(3) Extrapolate your best-fit line to the temperature axis to estimate the temperature at which the pressure would reach zero. Express this temperature in degrees Celsius and compare it to the accepted value of absolute zero, commenting on possible reasons for any discrepancy.
(4) Taking into account the stated measurement uncertainties, explain whether the scatter of the plotted points about the best-fit line is consistent with random error alone or suggests the presence of additional systematic effects.