Gas laws 112

Music:“Classical Gas”

by Mason Williams

Chem 112 Correlation of OWL scores & course grades

Clicker Question

What is the oxidation number of manganese in permanganate, MnO4

- ?

A.) -1

B.) -2

C.) +4

D.) +7

E.) 0

Pressure and Introduction to the Gas Laws

Galileo shows the Duke of Padua that water can only be pumped33 feet.Water cannot be raised more than 33 feet by any suction pump.

How to make a Torrichellianbarometer

Torrichelli proves the existence of a vacuum. When he tilts the tube the mercury fills the tube. When he raises the tube to upright, the mercury

falls to 760 cm leaving a vacuum above.

A portrait of Torricelli’s mentor, Galileo, hangs on the wall

Torricelli with his newly invented barometerIn Italian, “Torre” means “tower”.So, Torricelli means “little tower”.

Von Guericke’s vacuum pump & two hemispheres

Plaque honoring Boyle and Hooke at Oxford University, Oxford, England

Robert Boyle’s three-story water barometer

Pascal’s diagrams of apparatus for measuring air pressure and hydrostatic pressure.

Pascal’s brother-in-law, Perier

Graph of the data takenduring Perier’s ascent ofPuy de Dome.

MercuryBarometer

Antique Barometers

Pressure: the principle of snowshoes and ice skates

Pressure Units(three types)

US weather map with isobars

Derivation of formula for hydrostatic pressure

Water pressure

A range of pressure values for comparison

Capillary action, vacuum pumps, and barometers

How to read a manometer

Comparing barometer to manometers:

Absolute pressure vs. Relative pressure

(Gauge pressure)

We must use absolute pressure readings (and absolute temperature readings) in using the gas laws. Otherwise, our equations our equations become as complex (and even more complex) as the original Charles’ Law.

Compressed gas cylinder and its pressure regulator

How we store & utilize gas in lab

Lismore Castle, Irelandbirthplace of Robert Boyle

Robert Boyle (1637-1691)

An Ideal Gas Thermometer Use of absolute temperature

to simplify gas equations

Ideal gas law

Ten resulting equations (all part of PV = nRT)

The Universal Gas Law Constant, R(Universal because it works for all gases within the range of validity of the ideal gas law)

Meaning of the gas law constant, R

Some Applications

of the Gas Laws