20.1 Flashcards
(19 cards)
what is the pressure of a gas equal to
force per unit area that the gas exerts pressure normally (at right angles) on a surface
what is pressure measured in
Pa or Nm^-2
what does the pressure of a gas depend on
the temperature, the volume of the gas and the mass of the gas
what does boyles law state
for a fixed mass of gas at constant temp pV = constant
p= Pressure and V = gas volume
what does a volume scale of gas under pressure, a pressure gauge and a foot pump show
how the pressure of a fixed mass of gas depends on its volume when the temperature stays the same
what is any change at a constant temp called
isothermal change
what does pressure againts volume graph look like
a curve that tends towards each axis, as temperature increases it moves further away from the axis
what is an ideal gas
a gas that obeys Boyle’s law
what does plotting pressure against 1 over volume give
a straight line through the origin because p = constant 1/v when written in y = mx+c form
How can you find out how the volume of a fixed mass of gas at constant pressure varies with temperature
using a glass tube open at one end containing dry air trapped by a suitable liquid
by plotting the measurements of volume of the gas on the y axus and temp between 0 and 100 degrees what can you discover
the idea behind absolute 0
no matter how muchgas is provided as long as it is ideal its volume will be zero when
at 0K or at -273.15 degrees c
what can the relationship of charles law be written as
V/T = constant
what is any change at constant pressure called
isobraic change
what happens when work is done to change the volume of a gas
energy must be transferred by heating to keep the pressure constant
what can work done by gas on a piston be given by
work done = p delta V
What equipment shows how the pressure of a fixed mass of gas at constant volume can be measured at different temps
holder of dry air connected to a pressure gauge in a water bath over a heater
what happens if measurements of pressure againts t in kelvins a plotted on a graph
they give a straight line through the origin
what can the relationship of p and T be written as
p/T = constant
