Chapter 13: Gases

Question 1

Combined Gas Law

Answer 1

P1V1/T1=P2V2/T2; compares sample of gas at 2 moments in time; units must match and temperature must be in Kelvin

Question 2

Standard Temperature & Pressure (STP)

Answer 2

1.0 atm = 101.3 kPa = 760 mmHg
273 K

Question 3

Normal Boiling Point

Answer 3

Temp at which vapor pressure = 760 mmHg

Question 4

Boyle’s Law

Answer 4

PV=k

Question 5

Charles’s Law

Answer 5

V/T=k

Question 6

Gay-Lussac’s Law

Answer 6

P1/T1=P2/T2

Question 7

Ideal Gases

Answer 7

Always obey KMT; do not exist

Question 8

Avogadro’s Law

Answer 8

V=kn

Question 9

Ideal Gas Law

Answer 9

PV=nRT
P=Pressure (atm)
V=Volume (L)
n=# of moles
R=0.0821 (L*atm)
T=Temp (K)

Question 10

Real Gases

Answer 10

1. Collisions not elastic
2. Molecules have volume
3. Can change to liquids

Question 11

Real Gases Are Most Ideal When…

Answer 11

1. Temp increases (molecules have enough energy to break IMF)
2. Pressure decreases (molecules are less crowded & less likely to collide)
3. Molar mass decreases (weaker London Dispersion Forces)

Question 12

Density Using Ideal Gas Law

Answer 12

d = PM/RT
d=density (g/T)
P=Pressure (atm)
M=Molar Mass
R=0.0821 (L*atm)
T=Temp (K)