LBC Chapter 12 vocab working

number density

The number of gas

particles per unit volume;
used because the mass
of a gas doesn’t affect its

density

The blue gas has a higher number density
than the red gas, even though the red gas

has a higher mass

10 particles of He
gas, mass = 20 g

4 particles of C
gas, mass = 24 g

mole

A counting unit for molecules, ions

or particles

1 mole = 6.02 x 1023 objects, does

NOT depend on mass or volume

1 mole of various substances is

pictured to the left

Avogadro’s number

the

number of
particles
in a mole

standard temperature

and pressure (STP)

273 K
(0 oC)

1 atm

Dropdown

A gas at a pressure of 1 atm and 273 Kelvin ​

Select answer

at STP.

Avogadro’s law

The volume of a gas is
directly proportional to

the number of moles

under temperature and
pressure are constant.

ideal gas law

universal gas constant, R

Multiple Choice

The gas law that states that the volume of a gas is directly proportional to the number of moles under temperature and pressure are constant.

• combined gas law

• Avogadro's law

• ideal gas law

• law of conservation of mass

relative humidity

The amount of water

vapor in the air
compared to the

maximum amount of

water vapor possible for
a specific temperature,

expressed as a

percentage.