Properties of Gases

Views:
 
Category: Entertainment
     
 

Presentation Description

No description available.

Comments

By: honlethmamaril (8 month(s) ago)

goodmorning..how can i have a copy of this?

Presentation Transcript

Properties of Gases : 

Properties of Gases

Kinetic Molecular Theory : 

Kinetic Molecular Theory Gas particles can easily move past one another or move closer together because they are farther apart than liquid or solid particles. Gas particles in constant motion collide with each other and with the walls of their container. The kinetic-molecular theory states that the pressure exerted by a gas is a result of collisions of the molecules against the walls of the container.

Kinetic Molecular Theory : 

Kinetic Molecular Theory All particles that move have kinetic energy or energy of motion. Particles will have a higher kinetic energy (move faster) at higher temperature. As temperature increases, the seed of the gas particles will increase.

Kinetic Molecular Theory : 

Kinetic Molecular Theory The kinetic-molecular theory considers collisions of gas particles to be perfectly elastic; that is, energy is completely transferred during collisions. The total energy of the system, however, remains constant.

Properties of Gases : 

Properties of Gases When giving the volume of a gas, always give the pressure and temperature. Gas molecules are far apart so changes in pressure and temperature have large effects on the volume of a gas Remember, gases always fill the container.

Properties of Gases : 

Properties of Gases Solids and Liquids have molecules close together. Solids and Liquids have a fixed volume; it does not change when they are moved from one container to another. Changes in pressure and temperature do not affect solids and liquids as much as gases

Properties of Gases : 

Properties of Gases Measure volume in a container with markings. Graduated cylinder Eudiometer

Properties of Gases : 

Properties of Gases Units for volume measurement Milliliters (mL) Liters (L) Cubic centimeters (cm3) …

Properties of Gases : 

Properties of Gases Measure pressure of a gas Pressure gauge Barometer Sphygmomanometer for blood pressure …

Air Pressure : 

Air Pressure The scientific definition of pressure is “force divided by area.” Pressure may also be defined as the amount of force exerted per unit area of surface. To find pressure, you need to know the force and the area over which that force is exerted. Gases exert pressure by colliding with their surroundings.

Properties of Gases : 

Properties of Gases Units of pressure measurement psi – pounds per square inch Pascal (Pa) – newtons per square meter

Properties of Gases : 

Properties of Gases Units of pressure measurement psi – pounds per square inch Pascal (Pa) – newtons per square meter Inches of mercury mm of mercury = torr

Properties of Gases : 

Properties of Gases Measure temperature many different ways Thermometer – mercury (silver) or alcohol (red) inside Pyrometer – color something glows Thermister – electronic or digital thermometer

Properties of Gases : 

Properties of Gases Measure temperature many different ways Liquid crystals Bimetal …

Properties of Gases : 

Properties of Gases Units of temperature measurement ºF – Fahrenheit ºC – Celsius K – Kelvin (notice no º sign.) R - Rankine

Properties of Gases : 

Properties of Gases Change Celsius to Kelvin by adding 273 to the Celsius temp. ºC + 273 = K ºF + 459 = R

Properties of Gases : 

Properties of Gases Body Temp Room Temp Boiling point 37 ºC 25 ºC 100 ºC + 273 = 310 K + 273 = 298 K + 273 = 373 K

Properties of Gases : 

Properties of Gases Football Liquid N2 fever 291 K 177 K 313 K - 273 = 18 °C - 273 = -96 °C - 273 = 40 °C

Physical Models : 

Physical Models

Physical Models : 

Physical Models Dancers are particles, like molecules. Dancers are modeling the number of molecules.

Physical Models : 

Physical Models Dancers are modeling the number of molecules. The size of the room is the amount of space they have to dance in. Room size is modeling the volume of the gas.

Physical Models : 

Physical Models Dancers are modeling the number of molecules. Room size is modeling the volume of the gas. The beat of the music determines how fast the dancers dance. It indicates the speed of the dancers or molecules. Beat indicates temperature.

Physical Models : 

Physical Models Dancers are modeling the number of molecules. Room size is modeling the volume of the gas. Beat indicates temperature. The dancers colliding cause forces between the other dancers. Force is related to pressure. Collision rate refers to pressure.

Physical Models : 

Physical Models Dancers are modeling the number of molecules. Room size is modeling the volume of the gas. Beat indicates temperature. Collision rate refers to pressure.

Explaining Gases : 

Explaining Gases As the airplane goes up in the atmosphere, the pressure drops. Passengers are uncom- fortable because the pressure inside their bodies pushing outward is greater than the air pressure in the plane.

Explaining Gases : 

Explaining Gases Gas inside a can of pop has higher pressure to make the carbon dioxide dissolve in the liquid. When the can is opened, the pressure decreases until it is the same as the air pressure. The gas is now less soluble, and it bubbles.

Tennis Balls : 

Tennis Balls Container is pressurized to keep the balls from deflating on the shelf.

Explaining Gases : 

Explaining Gases As you go up in the atmosphere, the pressure drops. Your ears “pop” because the pressure inside your ear and outside your ear become the same.

Explaining Gases : 

Explaining Gases As the balloons go into the cooler temperature of the car, the volume decreases.

Explaining Gases : 

Explaining Gases Although the Pringle’s can has lower pressure in it to keep the chips fresh, there is some air in the can. At the top of the mountain where the outside pressure is even lower, the air in the can will actually push the seal out.

Explaining Gases : 

Explaining Gases The furnace will heat up the aerosol can. It could rupture/explode. The volume will get much bigger then.

Explaining Gases : 

Explaining Gases The beachball is filled with air. As the diver goes down into the ocean, the pressure gets higher. The ball will seem to deflate.

Explaining Gases : 

Explaining Gases The propane heater on a hot-air balloon heats the air in the balloon. It expands and become less dense so the balloon floats.