Ch 11 Section 2 Flashcards
Robert Boyle discovered that gas pressure and volume are
related mathematically
the observations of Boyle and others led to the development of the
gas laws
the gas laws are simple mathematical relationships between the
volume, temperature, pressure, and amount of a gas
Robert Boyle discovered that doubling the pressure on a sample of gas at constant temperature reduces its
volume by one-half
reducing the pressure on a gas by one-half allows the volume of the gas to
double
the pressure of a gas is caused by moving molecules hitting the
container walls
if volume of container is decreased but same number of gas molecules is present at the same temperature then there will be more molecules per
unit volume
the number of collisions with a given unit of wall area per unit time will …. and therefore…
increase as a result; pressure will also increase
plotting values of volume versus pressure for a gas at constant temperature gives a
curve
the general-volume pressure relationship illustrated is called
boyle’s law
boyle’s law states that the volume of a fixed mass of gas varies inversely with the pressure at
constant temperature
Boyle’s la can be expressed as : PV=
k
P is
pressure
V is
volume
k is a
constant
Since P and V vary inversely, their product remains the
same
because two quantities that are equal to the same thing are equal to each other, the relationship between changes of pressure and volume can be expressed as: P1V1 =
P2V2
P1 and V1 are
initial conditions
P2 and P2 are a
different set of conditions
given three of the four values P1, V1, P2, and V2, you can use this equation to calculate the fourth value for a
system at constant temperature
if pressure is constant, gases expand when
heated
when temperature increases, the volume of a fixed number of gas molecules must increase if the pressure is to
stay constant
at the higher temperature, the gas molecules move
faster