Gases and Gas Laws

Question 1

Properties of Gases?

Answer 1

• Particles traveling in straight line paths are randomly distributed
• No definite shape
• Space between particles is large
• Low density
• Can be compressed
• Can liquify at low temperature and at high pressure

Question 2

What are the units used in gas law?

Answer 2

Pressure - Standard pressure - 101.3kpa, 760 Torr, 1atm
Temperature - Standard temperature - 0 degrees/273K
Densities - Normally in g/L
Volume - Litres and millilitres

Question 3

What’s Boyles law? And it’s equation?

Answer 3

Volume occupied by a gas in inversely proportional to pressure exerted on the gas. (Va1/P)
Equation: P2V2=P1V1

Question 4

What’s Charles Law? And it’s equation?

Answer 4

Volume occupied by a gas is directly proportional to the kelvin temperature. (VaT(K))
Equation: V1/T1=V2/T2

Question 5

What’s the combined gas law? And it’s equation?

Answer 5

As temperature is decreasing it will decrease value for V1 (original volume) (Direct relationship)
Since pressure is decreasing it will increase value for V1 (inverse relationship)
Equation: P1V1/T1 = P2V2/T2

Question 6

What’s the ideal gas law? And it equation?

Answer 6

Unlike others it also takes into account the number of mols of gas.
Equation: PV=nRT
P = pressure (Atmospheres)
V = Volume (Litres)
n = x mols of Gas
T = Temperature (Kelvin or just K)
R = Universal Gas Law constant (.082atm/molK)

Question 7

What’s molar volume? And it’s equation?

Answer 7

Can be determined that one mol. of any gas at STP will occupy a volume of 22.4L.
STP/kPa = Standard temperature and pressure = 0 degrees/ and atm (atmospheric pressure) 101.3kPa

Question 8

What’s Avogadro’s hypothesis?

Answer 8

Equal volumes of gas under the same conditions of temperature and pressure will contain equal numbers of particles.

Question 9

How do you convert degrees to Kelvin and vice versa?

Answer 9

degrees > Kelvin you add 273

Kelvin > degrees you take away 273

Question 10

Units for Volume

Answer 10

Litres but in ideal gas law it varies

Question 11

Volume conversions?

Answer 11

1dm cubed = 1 litre

1m cubed = 1000 dm cubed = 1000000 cm cubed

Question 12

Units for pressure with conversions?

Answer 12

atm, kPa and in ideal gas law mainly Pa

1 atm. = 101.3kPa = 101325Pa

Question 13

Units for temperature with conversions?

Answer 13

Kelvin and degrees.

1 degree = 273 Kelvin

Question 14

Units for mols. with conversions?

Answer 14

mol., dm cubed

1 mol = 22.4 dm cubed.

Question 15

What are values at STP (standard temperature and pressure?

Answer 15

0 degrees or 273 Kelvin

1 atm or 101325 Pa

Question 16

Value for R? The universal gas law constant?

Answer 16

8.31441

Question 17

Ideal gas law’s equations and values?

Answer 17

PV = nRT
P = pressure atm/Pa
V = volume L/dm cubed
n = no. of mols of gas mol/dm cubed
T = temperature K
R = universal gas law constant = 8.31441

Question 18

Molar volume equation?

Answer 18

Comes from ideal gas law so same values and similar equation.
V = nRT/P

Question 19

Combined gas law equation and values?

Answer 19

P1V1/T1 = P2V2/T2

Question 20

Charles law equation with values?

Answer 20

V1/T1 = V2/T2

Question 21

Boyle’s law equation with values?

Answer 21

P2V2 = P1V1