Properties of Gases

Question 1

what are some common properties of gases?

Answer 1

volume changes with temp and pressure 
low viscosity 
low density under normal conditions 
gases are miscible 
compressible 
occupy the shape of containers quickly

Question 2

what is the defining characteristic of a gas?

Answer 2

the pressure they exert

Question 3

what is pressure exerted by a gase dependant upon?

Answer 3

the temperature of the gas
the amount of moles of the gas
the volume of the gas

Question 4

what is the formula for pressure?

Answer 4

force/area

Question 5

what two devices are used to measure pressure and how do they work?

Answer 5

barometer: competition between atmospheric pressure and gravity

Monometer: measures the pressure exerted from two gases

Question 6

what is the SI units for pressure?

Answer 6

Newton/Pascals … N/Pa

Question 7

what is boyles gas law?

Answer 7

at constant temp, the volume of a fixed amount of gas is inversely proportional to the applied(external) pressure

or P*V= constant of proportionality

Question 8

what is charles gas law?

Answer 8

at constant pressure, the volume of a fixed amount of gas is directly propertional to its absoulte temperature

or V/T= constant where temp is in kelvin

Question 9

what is avogadros gas law?

Answer 9

at fixed temperature and pressure, the volume of a gas is directly proportional to the amount, in moles, of gas

or V/N= constant

Question 10

what do you get when you combine all the gas laws?

Answer 10

the ideal gas law…

PV=nRT

where 
P=pressure
V=volume 
n=moles 
R= universal gas constant
T=temperature

Question 11

when a gas has a high density, what does this mean with reference to the individual atoms?

Answer 11

more dense= more collisions as the atoms travel shorter distances

Question 12

when a gas has a low density, what does this mean with reference to the individual atoms?

Answer 12

less dense= less collisions, travel greater dstiances

Question 13

all constituents of an ideal gas, whether atoms or moolecules…

Answer 13

act independently

Question 14

what is daltons law of partial pressures?

Answer 14

in a mixture of gases the total pressure exerted is the sum of the partial pressures that each gas would exert if it were alone under the same conditions

Question 15

what are mole fractions in a mixture of gases?

Answer 15

each component in a mixture contributes a fraction of the total number of moles in the mixture, the mole fraction (X) of that component