Paper 3 · ideal gases
Which graph shows the variation of volume of an ideal gas with temperature at constant pressure?
AExponential curve (volume increases rapidly with temperature)
BStraight line through origin (linear increase)
CCurve that flattens (volume increases then levels off)
DStraight line with negative gradient (volume decreases with temperature)
Explanation: The marking scheme gives answer B. By Charles's Law, V ∝ T (at constant pressure), which gives a straight line through the origin when plotted against absolute temperature.
ZIMSEC Chemistry Paper 3, November 2009, Q7