1.3

Question 1

Express the Ideal Gas Law

Answer 1

PV=nRT

Question 2

what is the ideal gas law?

Answer 2

It is an:
- empirical law: based on experimental observations
- explains the behavior of gases over a limited range of conditions
-macroscopic explanation: does not describe microscopic behavior of particles in gas
V~ nT/P
- most simple gases exhibit nearly ideal gas behavior at ordinary temperatures and pressures

Question 3

What does R stand for and what is its value?

Answer 3

• R is the universal gas constant

- R= 8.314J mol-1 K-1

Question 4

When one of the variables have changed; and you are given only two variables eg. P and T; and T was changed; should you use ideal gas law equation of another law?

Answer 4

another law, which is gay lussacs’ law
find T2 by
P1/T1 = P2/T2
(because only one variable was changed and that they weren’t asking for an unknown (that’s when the ideal gas law is used))

Question 5

true or false the density of a gas is proportional to molar mass?

Answer 5

true

d~M

Question 6

find M using the ideal gas law

Answer 6

d= m/V= PM/RT
M= dRT/P

Question 7

express density (g L-1 in gas)

Answer 7

mass/volume

Question 8

What is Dalton’s law of partial pressures?

Answer 8

total pressure of gas mixture is sum of the partial pressures of individual gases in the mixture

Question 9

What causes partial pressure?

Answer 9

due to pressure exerted by unreacting gases in a gas mixture

Question 10

why does a hot air balloon rise?

Answer 10

n~ 1/T
when V and P are fixed
(substances of low density float on substances of high density; hot air is less dense than cold air)

Question 11

true or false: each gas in a mixture is considered independent?

Answer 11

true

Question 12

true or false: all gases in mixture have the same V and T

Answer 12

true

Question 13

true or false: the kinetic molecular theory, states that particles in gas behave independently

Answer 13

true

Question 14

true or false: all gases in mixture have volume of container

Answer 14

true

Question 15

how do you determine the partial pressure of a gas?

Answer 15

multiply the total pressure of mixture by fractional composition of the gas

Question 16

express dalton’s law of partial pressures

Answer 16

P total= n total (RT/V); assume that our gas mixture occurs at the same volume and temperature

Question 17

How do you collect a gas?

Answer 17

by displacing water from a container

Question 18

true or false; when temperature increases, vapor pressure of water increases

Answer 18

true

Question 19

gas mixtures in contact with WATER; how does dalton’s law of partial pressures apply?

Answer 19

when a gas is in contact with water, the total pressure is the sum of the gas pressure AND the vapor pressure of water at the given temperature

Question 20

what dos vapour refer to?

Answer 20

a sample of gas above a liquid

Question 21

true or false : water vapor also occurs in collected gas?

Answer 21

true

Question 22

true or false: partial pressure of water vapor (vapor pressure) DEPENDS ONLY ON TEMPERATURE?

Answer 22

true

Question 23

If asked to find the partial pressure of dry gas (take away the partial pressure of water vapor from the total pressure)

Answer 23

…yep