The Mole, Avogadro & The Ideal Gas Equation PHYSICAL

Question 1

What is the Avogadro constant?

Answer 1

The number of particles equivalent to the relative atomic mass of a substance

Question 2

What value is the Avogadro constant?

Answer 2

6.02 x 10²³ g mol⁻¹

Question 3

What is a mole?

Answer 3

The mass of a substance containing the same number of atoms in 12g of carbon-12, equal to Avogadro constant

Question 4

How are moles, particles and Avogadro’s constant linked?

Answer 4

Particles = Moles x Avogadro’s constant
Moles = Particles / Avogadro’s constant
Avogadro’s constant = Particles / Moles

Question 5

How can the number of moles of a substance be calculated?

Answer 5

By dividing mass of substance by molar mass

Question 6

What is concentration of a solution?

Answer 6

The amount of solute dissolved in a solvent to make 1dm³ of solution

Question 7

What is a solute?

Answer 7

A substance that dissolves in a solvent to form a solution

Question 8

What is a solvent?

Answer 8

A substance that dissolves a solute to form a solution

Question 9

How can concentration be calculated?

Answer 9

By dividing moles of a solute by the volume of the solution

Question 10

What is a concentrated solution?

Answer 10

Solution with high concentration of solute

Question 11

What is a dilute solution?

Answer 11

Solution with a low concentration of solute

Question 12

What units are used for calculations involving concentration?

Answer 12

Moles not grams
dm³ not cm³

Question 13

What is Avogadro’s hypothesis?

Answer 13

Suggestion that equal volumes of gases contain the same number of molecules

Question 14

What is the volume of one mole of any gas at room conditions?

Answer 14

24.0 dm³

Question 15

What is room temperature?

Answer 15

20 degrees celcius

Question 16

What is room pressure?

Answer 16

1 atmosphere

Question 17

How can the molar gas volume be used to find volume of gas?

Answer 17

amount of gas in moles x 24

Question 18

How can the molar gas volume be used to find the mass or moles of a gas?

Answer 18

volume of gas / 24

Question 19

What does the kinetic theory of gases state?

Answer 19

Molecules in gases are constantly moving

Question 20

What five assumptions does the kinetic theory of gases make?

Answer 20

Gas molecules are moving fast and randomly
Gas molecules hardly have any volume
Gas molecules do not attract or repel each other
No kinetic energy is lost when gas molecules collide
Temperature of gas is related to average kinetic energy of molecules

Question 21

What are ideal gases?

Answer 21

Gases that follow the kinetic theory of gases

Question 22

What does the volume of an ideal gas depend on?

Answer 22

Pressure
Temperature

Question 23

What affect does temperature have on ideal gas?

Answer 23

Particles gain more kinetic energy and more frequent collisions with container wall

Question 24

How is the volume of an ideal gas directly proportional to temperature at constant pressure?

Answer 24

Molecules get further apart to keep pressure constant and volume increases

Question 25

What happens to real gases at low temperature and high pressure?

Answer 25

Molecules close to each other Dipole forces between molecules Attractive forces pull molecules away from container wall Volume of molecules not negligible

Question 26

What assumptions do real gases disobey at low temperature and high pressure?

Answer 26

Zero attraction between molecules Volume of gas molecules can be ignored

Question 27

What is the ideal gas equation?

Answer 27

PV = nRT

Question 28

What does P stand for in PV = nRT?

Answer 28

Pressure

Question 29

What does V stand for in PV = nRT?

Answer 29

Volume

Question 30

What does n stand for in PV = nRT?

Answer 30

number of moles of gas

Question 31

What does R stand for in PV = nRT?

Answer 31

Gas constant

Question 32

What does T stand for in PV = nRT?

Answer 32

Temperature

Question 33

What is P measured in in PV = nRT?

Answer 33

Pascals (Pa)

Question 34

What is V measured in in PV = nRT?

Answer 34

m³

Question 35

What is n measured in in PV = nRT?

Answer 35

Moles

Question 36

What is R measured in in PV = nRT?

Answer 36

8.31 JK⁻¹ mol⁻¹

Question 37

What is T measured in in PV = nRT?

Answer 37

Kelvin (K)