Gas Laws: Boyles Law Charless Law Combined

1
Gas LawsBoyles Law Charless LawCombined
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Boyles Law

• Volume and pressure are indirectly proportional.
• P1V1 P2V2

3
Application

• 53.6 ml of a gas is held at a pressure of 0.97
  atm
• The pressure is changed to 2.30 atm but the
  temperature remains constant

What happens to the volume?
Decreases to 23 mL
4
Application

• 250. ml of oxygen gas is collected at STP
• The temperature remains standard but the pressure
  changes to 802 mm Hg

What happens to the volume?
Decreases to 236 mL
5
Application

• 43.8 ml of helium is held at standard temperature
  and pressure
• The temperature is not changed, but pressure
  drops to 629 mm Hg

What happens to the volume?
Increases to 52.9 mL
6
Charless Law

• Volume and Kelvin temperature are directly
  proportional.
• P1 P2
• T1 T2

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Application

• A gas with a volume of 354 ml is at standard
  temperature
• The temperature is raised to 345 K and the
  pressure is held constant

What happens to the volume?
Increases to 447 mL
8
Application

• 500. cm3 of hydrogen gas is collected at 20.0 oC
• The pressure remains unchanged but the
  temperature lowers to 9.0 oC

What happens to the volume?
Decreases to 481 mL
9
Application

• A gas with a volume of 95.6 cm3 is held at
  43 oC
• The temperature is changed to 326 K but the
  pressure is not changed

What happens to the volume?
Increases to 98.6 mL
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Combined Gas Law

• When more than one variable is changing . . .
• P1V1 P2V2
• T1 T2

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Application

• 100. cm3 of gas is held at 323 K and 1.00 atm
  pressure
• The temperature is changed to 301 K and the
  pressure decreases to 0.500 atm

What happens to the volume? Which law is it?
Increases to 186 mL Combined Law
12
Application

• 84 ml of gas is held at a pressure of 758 mm Hg
  and 10.0 oC
• The temperature increases to 50.0 oC and the
  pressure changes to 770 mm Hg

What happens to the volume? Which law is it?
Increases to 94 mL Combined Law
13
Application

• 2.4 ml of neon is held at STP
• The new pressure is 1.0 atm and the new
  temperature is 273 K

What happens to the volume? Which law is it?
No change in volume no change in conditions
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Application

• 1.00 L of gas is collected at a pressure of 1.0
  atm and a temperature of -34 oC
• The conditions change to STP.

What happens to the volume? Which law is it?
Increases to 1.14 L Charless Law