Chapter - 11 Gases

Question 1

Kinetic Molecular Theory

Answer 1

a model for gases where gases are composed of widely spaced, noninteracting particles whose average kinetic energy depends on temperature

Question 2

Pressure

Answer 2

P= force/area

- results from the constant collision of gas particles w each other and the surfaces around them

Question 3

Gas Laws

Answer 3

gas laws shows how one of the properties of a gas varies with another

Question 4

Combined Gas Law

Answer 4

Boyle’s law + Charles’ law

(P1V1)/T1=(P2V2)/T2

Question 5

Ideal Gas Law

Answer 5

combines 4 properties of gas:
P -pressure
V -volume
T -temperature
n -# of moles

PV=nRT

Question 6

Boyle’s Law

Answer 6

P and V are inversely proportional
-inc in P, dec in V

constant=PV
P1V1=P2V2

Question 7

Charle’s Law

Answer 7

V/T or
V1/T1=V2/T2
-vol + temp are directly proportional
-inc in vol, inc in temp

Question 8

Kinetic Molecular Theory Assumption

Answer 8

1 gas is a collection of particles (atoms or molecs) in constant, straight-line motion
2 gas particles DO NOT attract/repel each other. They DO collide/bounce off each other
3 there’s a lot of space be gas particles in comparison to their size
4 avg kinetic energy (motion energy) is proportional to temp of gas (in Kelvins)

Question 9

1atm = ____mm Hg

Answer 9

1 atm = 760 mm Hg

Question 10

Kinetic molecular energy Predictions

Answer 10

1 gas is compressible
2 assume the shape + volume of their container
3 low densities compared to liq or solid

Question 11

units of pressure

+ conversions

Answer 11

a. pascal (Pa)
Pa is equal to a Newton per square meter
1 Pa = 1 N/m2

b. 1 atmosphere (atm)
1 atm = 101,325 Pa

c. millimeter of mercury (mmHg)

1atm=760mmHg

Question 12

SI unit of pressure

Answer 12

pascal (Pa)

Question 13

atmosphere (atm)

Answer 13

unit of pressure

-avg pressure at sea level

Question 14

mm Hg

Answer 14

millimeter of mercury is a unit of pressure

-how pressure is measured with a barometer

Question 15

Barometer

Answer 15

-mercury is pushed up to a height of 760mm by avg pressure at sea level (atm)

in other words,
1 atm = 760 mmHg

Question 16

torr

Answer 16

1 mm of Hg

Question 17

Avogadro’s Law

Answer 17

vol of gas and amount of gas in moles (n) are directly proportional
V1/n1=V2/n2

Question 18

ideal gas constant

Answer 18

R=0.0821 Latm/moleK

Question 19

Partial Pressure

Answer 19

fractional composition is the percent composition divided by 100
Ppressure=fractional composition x total pressure

ex) what is partial pressure of Nitrogen gas in air at 1atm if N is 78%, O is 21%, and Argon is .9%

P(N2)=0.78 x 1atm
=0.78atm
P(O2) = 0.21 x 1atm
=0.21atm

Question 20

Dalton’s Law of Partial Pressure

Answer 20

the sum of the partial pressures of each component in a gas mixture must equal the total pressure

Ptot=Pa+Pb+Pc+…

Question 21

Vapor Pressure

Answer 21

partial pressure of water in a mixture

-depends on temp (inc in temp is inc in vapor pressure)

Question 22

Standard Temperature and Pressure

STP

Answer 22

the volume occupied by 1 mol of gas at 0C(273.15K), and 1atm is 22.4 L

Question 23

Molar Volume

Answer 23

1 mol of any gas at STP occupies 22.4L

1mol=22.4L