Summary

#### Atomic Theory

“All things are made up of atoms.”

#### States of matter

Solid, liquid, gas, and plasma

#### State of Solids

• Has definite shape and volume
• High density and not very compressible
• Does not depend on the shape of the container (doesn’t fill it in)

#### State of Liquids

• Has a fixed volume
• Takes the shape of container
• Less dense than solids
• Almost incompressible

#### State of Gases

• Takes the shape of the container
• Takes the volume of container (this means that the gas molecules can be spread out evenly in the container or compressed in a smaller container. The volume is when the molecules are evenly distributed.)
• Can be compressed
• Gases are in the gaseous state at room temperature
• Gases have more energy than liquids, and solids.
• Gases are less dense.

#### State of Plasma

Plasma is simply an ionized gas, where the gas is charged with free electrons and positive ions because of the amount of energy plasma contains.

## Unit 2.3 – Describe the various units used to measure pressure and conversions

There are several units that pressure is measured in.  The unit Pascal is the S.I unit is equivalent to 1 N per square metre. To compare the unit Pascal to Atmosphere pressure of Atm, 101.3 kPa is for 1 Atm. In addition, the unit Torr named after Torricelli is equivalent to the amount of mercury displaced by the mercury barometer of 760mm, therefore 760 Torr = 760mm of Hg.  For simplicity sake, all units can be compared to 1 Atmosphere, which is equivalent to 760 mm of Hg, 760 Torr, 101.3kPa, and 14.7 Psi.

 Unit Compared to 1 atm Compared to 1 kPa KPa 1 atm = 101.3 kPa mmHg 1 atm = 760 mmHg 1 kPa = 7.501 mmHg torr 1 atm = 760 torr 1 kPa = 7.501 torr psi 1 atm = 14.7 psi 1 kPa = 0.145 psi atm 1 kPa = 0.009869 atm

To convert an unit, since they are all proportional, use dimensional analysis to convert the units.

Converting 160kPa to all other units…

160kPa  = 1.58atm