(Ch. 11) Gases

Question 1

What is Atmospheric Pressure?

Answer 1

The force exerted by the atmosphere on a given surface.

Question 2

What is the relationship between Atmosphere and Hg? Torr and Hg?

Answer 2

1 atmosphere= 760mm Hg
&
1 torr = 1 mm Hg

Question 3

What are the three properties of gas that he reviewed?

Answer 3

1. Gas has no fixed volume
2. Gas can be compressed
3. Gas has low density

Question 4

What causes “Pressure?”

Answer 4

Pressure is caused by the constant collisions of atoms and molecules in a gas with each other and the surfaces around them.
(ex. Gas molecules stuck in a tire)

Question 5

Gases have high _____ energy.

Answer 5

Kinetic

Question 6

What is Boyle’s Law?

Answer 6

My Def: Boyle’s Law describes an inverse and proportional relationship between volume and pressure regarding gas.

Prof Def: The volume of a gas at a constant temperature and moles (amount) of gas is inversely proportional to the pressure.

Question 7

What is the equation that describes the relationship evident in Boyle’s Law?

Answer 7

[V~1/p]- This describes that as volume increases, pressure decreases, and so on.
[P1V1=P2V2]- If we are missing one value, we can use the proportional relationship to find it, given the other values.

Question 8

Describe Charles’ Law.

Answer 8

My Def: As temperature increases, the volume of a gas increases proportionally. But only when the pressure and amount of gas do not change.

Prof Def: The volume of a gas, at constant (P) and (n), is directly proportional to its absolute temp.

Question 9

What does “absolute temperature” mean?

Answer 9

Units of Kelvin

Question 10

What is the equation used to convert Celsius to Kelvin?

Answer 10

C+273.15=K

Question 11

What is the equation that best describes Charle’s Law?

Answer 11

V1/T1=V2/T2

Question 12

Describe Avogadro’s Law.

Answer 12

My Def: More volume= more moles of said gas IF temp and pressure are constant.

Prof Def: The volume of a gas at constant temperature and pressure is directly proportional to the number of moles of gas.

Question 13

What equation best describes Avogadro’s Law?

Answer 13

V1/n1=V2/n2

Question 14

How do we write the number of particles/ moles?

Answer 14

(n)

Question 15

What is the Combined Gas Law?

Answer 15

This equation describes how volume, pressure, and temperature all react together.
Either:
1. V decreases, T/P increase
2. T/P increase, V decreases

Question 16

What equation describes the Combined Gas Law?

Answer 16

(P1)(V1)/T1= (P2)(V2)/T2

Question 17

What is an Ideal Gas?

Answer 17

An ideal gas refers to a hypothetical gas whose pressure, volume, and temperature relationships are completely described by the ideal gas equation/law.

Question 18

What is the Ideal Gas Equation?
What does each letter represent?

Answer 18

1. PV=nRT
2. Pressure, Volume, Moles, Gas Constant, Temp.

Question 19

If R is a gas constant, what is its numerical value?

Answer 19

R= 0.082 Liters of Atmosphere/mol(K)

Question 20

For the ideal gas law, what must the X be in units of?
1. Pressure
2. Volume
3. n
4. Temperature

Answer 20

1. Atmosphere
2. Liters
3. Moles
4. Kelvin

Question 21

What is Dalton’s Law?

Answer 21

The sum of the partial pressures of each component in a gas mixture must equate to the total pressure.

Question 22

How many mm are in an inch?

Answer 22

25.4mm = 1 inch

Question 23

How many g are in a L?

Answer 23

1000g = 1 Liter

Question 24

How do you find molar mass?

Answer 24

Mass (g)/ Number of moles (mol)
(You could also find the molar mass of a compound by adding the known atomic masses of each element)