Amount of Substance

Question 1

Define relative atomic mass

Answer 1

Average mass of an atom compared to 1/12 mass of a carbon-12 atom

Question 2

Define relative molecular mass

Answer 2

Average mass of a compound compared to 1/12 mass of a carbon-12 atom

Question 3

Define Avogadro’s constant

Answer 3

Number of particles in one mole of a substance

Question 4

How would you calculate % yield?

Answer 4

% yield = actual mass of product / expected mass of product

Question 5

How would you calculate atom economy?

Answer 5

Atom Economy = Mr of useful product / Mr of reactants

Question 6

What’s the ideal gas equation?

Answer 6

PV = nRT
Pressure (Pa) x vvolume (m3) = moles x gas constant (8.31) x temperature (K)

Question 7

What’s the equation that links moles, concentration and volume?

Answer 7

Moles = concentration x volume

Question 8

What’s the equation that links moles, mass and Mr?

Answer 8

Moles = mass / Mr

Question 9

Define empirical formula

Answer 9

Simplest whole number ratio of atoms in a compound

Question 10

What are the standard conditions?

Answer 10

Temp = 298K (25C)
Pressure = 100kPa (atm)