Gas laws
Download
1 / 31

Gas Laws - PowerPoint PPT Presentation


  • 129 Views
  • Uploaded on

Gas Laws. Solid - Molecules are held close to each other by their attractions of charge. They will bend and/or vibrate, but will stay in close proximity.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Gas Laws' - nitza


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  • Solid - Molecules are held close to each other by their attractions of charge. They will bend and/or vibrate, but will stay in close proximity.

  • Liquid - Molecules will flow or glide over one another, but stay toward the bottom of the container. Motion is a bit more random than that of a solid.

  • Gas - Molecules are in continual straightline motion. The kinetic energy of the molecule is greater than the attractive force between them, thus they are much farther apart and move freely of each other.


Nature of gases
Nature of Gases

  • No definite shape nor volume

  • Low density

  • Compressibility

  • Diffusion



Diffusion
Diffusion

  • Which molecules diffuse quicker?

    • Heavy, large

    • Light, small


Kinetic molecular theory
Kinetic Molecular Theory

  • Gases consist of large numbers of tiny particles that are far apart relative to their size

  • Collisions between gas particles and between particles and container walls are elastic (no loss of energy)

  • Gas particles are in continuous, rapid, random motion



Pressure
Pressure

  • Force per unit area on a surface

  • Pressure =force/ area



Atmospheric pressure
Atmospheric Pressure

  • Weight of gases that compose the atmosphere

    • 78% nitrogen

    • 21% oxygen

    • 1% other gases


Ears pop in airplane
Ears “pop” in airplane

  • Density and pressure of air is lower

  • Air pressure inside ears changes to reach same pressure as air in cabin (6,000-8,000 ft above sea level)

  • Pressurized

    cabin


Measuring pressure
Measuring Pressure

  • Barometer- device to measure atmospheric pressure



Standard pressure
Standard pressure

  • 760 mm of mercury (760 torr)

  • 1 atmosphere (atm)

  • 101.3 kilopascals (kPa)



Practice question
Practice Question

  • The average atmospheric pressure in Denver, Colorado is 0.830 atm. Convert this to mm of Hg and kPa.

    0.830 atm x 760 mm Hg = 631 mm Hg

    1 atm

    0.830 atm x 101.3 kPa = 84.1 kPa

    1 atm


Gases collected by water displacement
Gases collected by water displacement

  • Gas produced by reaction displaces water which is more dense


Dalton s law of partial pressure
Dalton’s Law of Partial Pressure

  • Pressure of each gas in a mixture is called partial pressure

  • Dalton’s law states that the total pressure of a gas mixture is the sum of the partial pressures of the component gases

    PT= P1 + P2 + …


Gas laws1
Gas Laws

  • Boyle’s Law

  • Charles’ Law

  • Gay-Lussac’s Law


Boyle s law
Boyle’s Law

  • Pressure-volume relationship

  • Inverse relationship


  • PV= k

  • P1V1= P2V2

  • A sample of oxygen has a volume of 150.0 mL when its pressure is 0.947 atm. What will the volume of the gas be at a pressure of 0.987 atm if the temperature remains constant?

  • (0.947 atm)(150.0 mL)=(0.987 atm) V2

  • V2= 144 mL


Charles law
Charles’ Law

  • Volume- temperature relationship

  • Direct relationship

  • V = k

    T

  • V1 = V2

    T1 T2

Always use Kelvin temperature



Gay lussac s law
Gay-Lussac’s Law degrees Celsius. What volume will the gas occupy at 50 degrees Celsius if the pressure remains constant?

  • Pressure-temperature relationship

  • Direct relationship

  • P = k

    T

  • P1 = P2

    T1 T2

Always use Kelvin temperature



Combined gas law
Combined Gas Law degrees Celsius. What would the gas pressure in the container be at 52 degrees Celsius?

  • If something is constant in the problem, it can be canceled out




Scuba
SCUBA atm. What pressure is needed to reduce the volume at constant temperature to 50.0 mL?

  • Gas Laws WebQuest


ad