Gases and the atmosphere

unit 3 of chem 30s

what is kPa at STP

101.325 kPa

what is mb at STP

1013.25mb

what is mmHg at STP

760mmHg

what does the term pressure mean?

The amount of force exerted on a certain space ( force per unit area )

what is a barometer?

an instrument that measures the pressure of the atmosphere

why do barometers used mercury?

Used because of its high density

what is a manometer

both ends are open, and measures the difference in levels of Hg in pressure in between gas and air

what is the difference between a manometer and a barometer

a barometer measures the change in pressure, while a monometer compares the difference in pressures

how is using a straw similar to a barometer?

the pressure of the atomosphere pushes downward, when you suck through he straw the pressure in you body decreases. This creates a vaccum

how do barometers work

the weight of the liquid (mercury) is pulled down by the pressure of the atmosphere and pushed into the inner tube. a vaccum pulls up the liquid which raises the level.

what happens if theres higher pressure in a barometer

the Hg rises

what happens is theres lowers pressure in a barometer

the Hg lowers

who first used the barometer

Torricelli in 1643

what is the atmosphere

the mass of air surrounding the earth

what is the composition of the atmosphere

-N2: 78% -O2: 21% - H2O: 2% CO2 and Ar: 0.98%

what are the different eras of the atmosphere

Origin, Chemical Era, Microbial Era, Biological Era

what era is the atmosphere currently in

the Biological Era

how many mass extinctions have there been

5

what are sources of oxygen

Oxygen is created through photo synthesis and is in the atmosphere, created when H2O particles split

what is the ozone layer

Filters out high damaging levels of radiation from the sun. Which led to more complex species.

What happened to CO2 levels over time

They Increases

what is Boyles law relationship

As pressure increases, volume decreases. This is an inverse relationship

Who created Boyles law and where was he born

named after Robert Boyle, he was born in Ireland

what is the formula for Boyles Law

P1 V1= P2V2

what factor can affect boyles law

If temperature isn’t constant, Boyles law wont work

what must you check when solving all gas law questions

always make sure the gas units are the same!

a balloon is sqeezed and the air inside becomes compressed. What gas law is displayed

Boyles Law

What is Charles Law relationship

As volume increases, temperature increases. This is a direct relationship

If a balloon is heated up, the particles expand causing the balloon to become bigger. Which gas law is this

Charles law

Who was Charles law named after and where was he from

Jaques Alexandre Cesar Charles, from france

what is the formula for Charles Law

V1/ T1 = V2/ T2

what must be contant in order for charles law to work

pressure

what is 0°c in kelvin

273.15 K

what is the relationship in Gay Lussacs Law

When pressure increases, Temperature increases, this is a direct relationship

What was Gay Lussac’s Full name

Joseph-Louis Gay-Lussac

Whats the Formula for Gay Lussac Law

P1/T1 =P2/T2

Avogadros Theory

Equal volumes of gases at the same temp and pressure contain equal numbers of molecules

molar volume

The volume that one mole of gas occupies at a specific T and P. This volume is dependent on T and P

What is the molar volume at STP

22.4L