Flashcards in Unit 2 - Gas Deck (74):

1

## Gasses are compressible; meaning what?

### That pressure increases as volume decreases..

2

## Why do gasses expand as temperature increases?

### The more heat; the more space is taken up because they move faster and more often and farther

3

## When a gas is confined what happens when the temperature increases

### the pressure increases

4

## when a gas is not confined what happens when temperature increases

### the volume/amount of space the gas takes up increases

5

## gasses have low densities meaning what

### very low physical weight, weigh like nothing

6

## gasses are miscible; meaning what

### they mix evenly and completely, so the CO2 spreads evenly throughout the world and there isnt more Co2 in some places compared to others

7

## gasses have no shape or volume what do they do

### they take the shape of the container they are in

8

## what does the Kinetic Molecular Theory say

### all particles are in motion at all times

9

## what is an ideal gas

### hypothetical gas that has perfect characteristics

10

## characteristics of an ideal gas

###
-gas molecules are in constant random motion that moves in a straight line until they bounce back off the wall of a container or molecule (they go back and forth in a straight line bouncing off things)

-gas molecules have a mass but no volume

-the only interaction between gas and container are collisions where kinetic energy is conserved

11

## what are point masses

###
they have a mass but no volume

IDeAL GASSES have A POINT MASS

12

## what are elastic collisions

### collisions where kinetic energy is conserved IDEAL GASSES HAVE ELASTIC COLLISIONS

13

## real gasses do not have these perfect characteristics however

### their behaviour is not that different from an ideal gas

14

## real gasses slow down over time; why?

### because of friction; instead of bouncing back and forth at a constant rate and force like ideal gasses, over time after each bounce the gas loses force and slows down

15

## friction is not involved in what gasses

### ideal gasses

16

## what creates our atmosphere

### the earths gravitational pull keeps gas molecules near the surface of the planet

17

## what is pressure

### force per unit area... force/area

18

## pressure is exerted where and how much

### in all directions to the same extent

19

## what is atmospheric pressure

### force that air exerts in a particular area on the Earths surface

20

## air is less compressed as ...

### altitude increases (the height) the higher you get air is less compressed

21

## because air is less compressed the higher you go that means...

### less pressure is exerted the higher you get

22

## Pascal and Perier used Hg to prove ...

### atmospheric pressure decreases with altitude

23

## the work of pascal, perier and torricelli all led to the development of

### the mercury barometer

24

## what are the several different units used to measure pressure

###
mmHg or torr

Pa

kPa

atm

bar

25

## whats mmhg or torr

### millimeters of mercury; (760)

26

## whats kPa and Pa

### pascal and kilopascal.. kPa is 101.325

27

## whats atm

### atmospheric pressure ; (1)

28

## 1 bar = how many kPa

### 100

29

## how to convert

### w/g = w/g.. multiply first bottom by second top and divide by second bottom to get first top.. then use sig digs

30

## who discovered boyles law

### irish scientist robert boyle

31

## what was robert boyle studying

### relationship between pressure and volume of gases at constant temperatures

32

## pressure on the walls of a container is caused by

### collisions of gas molecules with the walls

33

## as you reduce the volume of contained gas (make the container smaller), there is less room what happens

### they collide with the walls more .. more collisions = higher pressure

34

## _____ collisions = _______ pressure

### more = higher

35

## boyles law graph ; volume vs pressure for a gas graph... how does it work

###
title: volume vs pressure for a gas

Y axis: responding (volume L)

x axis: manipulated (pressure kPa)

THE LINE GOES DOWN FROM LEFT TO RIGHT

BAD BOYLE = GOES DOWN

36

## boyles law states

### the volume of gas varies inversely with the pressure at a constant temperature and mass... PRESSURE AND VOLUME CHANGE: TEMP AND MASS STAY SAME

37

## examples of boyles law

###
breathing/lungs; inhale we increase the volume of our chest with decreases pressure allowing more air to move in...

the deeper in the ocean you go the more pressure is around you which makes you want to breath out

38

## BOYLES LAW EQUATION

###
P1V1=P2V2

Pressure= kPa

Volume= L

39

## GRAphing volume vs temperature

###
goes up from left to right; linear.

Title: volume vs temperature for a gas

Y axis: Volume (L)

X axis: Temperature in K or C

***When the temp is in K the line starts at the corner of the graph at 0K but when in C it starts farther up because there are negatives in C it would start at -273.15C and go up from there

40

## the temperature is what when the volume of a gas is zero

### -273.15C which is 0 Kelvin

41

## what is absolute zero

### 0 Kelvin and -273.15 Celcius

42

## WHo created absolute zero

### Lord Kelvin in 1848

43

##
t is used for temperature in _____

T is used for temperature in ____

###
t = C

T = K

44

## how do you go from C to K

### you add 273.15 to your Celcius number.. aka 25C + 273.15 = 298.15K

45

## how do you go from K to C

### you subtract 273.15 from your Kelvin number.. aka 298.15K - 273.15 = 25C

46

## Who noticed there was a relationship between temperature and volume of gas

### Jacques Charles and Joseph Louis Gay-Lussac

47

## Charles law stuff: as temperature increases so does..

### the kinetic energy of the gas molecules

48

## charles law stuff: as molecules move faster, they...

### exert higher pressure

49

## charles law stuff: the volume of a gas will expand under this pressure until it reaches

### atmospheric pressure

50

## charles law states

### that the volume of gas varies directly with the temperature at a constant pressure and mass.. VOLUME AND TEMPERATURE CHANGE AND PRESSURE AND MASS ARE CONSTANt

51

## whats constant in charles law

### pressure and mass

52

## what changes in charles law

### volume and temperature

53

## whats constant in boyles law

### temperature and mass

54

## what changes in boyles law

### volume and pressure

55

## CHarles LAW EQUATION

###
V1/T1=V2/T2

T= temp. in K

V= Volume in L

56

## how do you go from mL to L

### mL#/1000 = L

57

## whats STP

###
standard pressure and temperature

=0C/273.15K and 101.325 kPa

58

## Whats SATP

###
standard ambient temperature and pressure

=25C/298.15K and 100 kPa

59

## Equation for Combined Gas LAw (charles and boyles combined)

###
(P1)(V1)/T1 = (P2)(V2)/T2

pressure in kPa

Volume in L

Temp in K

60

## who studied combining volumes of gases

### Gay-Lussac

61

## About Combining volumes of gases

###
-chemical reactions involving gases

-studied the volumes og gas reactants and products

-gases combine in very simple proportions

62

## the law of combining volumes states

### that when gases react, the volumes of the gaseous reactants and products measured at constant temperature and pressure are always in whole number ratios

63

## Equation for combining volumes of gases

###
V1/N1 = V2/N2

v1 is the volume given

n1 would be the number of mols of the gas with the given volume

v2 would be the volume your looking for

n2 is the number of moles of the gas your looking for

64

## example of law of combining volumes

###
n2 + 3h2 -> 2nh3

1:3:2 is the ratio

for every one mole of nitrogen gas and 3 moles of hydrogen gas , 2 moles of ammonia gas is produced

65

## whats the ideal gas law

### combines all four variables P, V n and T into one equation

66

## Ideal Gas Law Equation

###
PV =nRT

pressure in kpa

volume in L

n= number of moles in mol

R=universal gas constant (8.314)

Temperature in K

67

## ammonia

### NH3

68

## ozone equation

### O3

69

## sucrose

### C12H22O11

70

## methane

### CH4

71

## glucose

### C6H12O6

72

## hydrogen sulphide formula

### H2S

73

## ethane

### C2H6

74