Amount of substance ( AS )

Question 1

define relative molecular mass

Answer 1

the average mass of a molecule relative to 1/12th the mass of a Carbon-12 atom

Question 2

define relative atomic mass

Answer 2

the average mass of an atom relative to 1/12th the mass of a Carbon-12 atom

Question 3

define the Avogadros constant

Answer 3

number of particles/atoms in one mole of a substance

Question 4

write the equation that links mass of 1 mole, mass of 1 atom and avogadros constant

Answer 4

mass of 1 mole=mass of 1 atom X avogadros constant

Question 5

define percentage yield

Answer 5

the percentage of a product formed in a reaction compared to a theoretical maximum

Question 6

how do you calculate percentage yield?

Answer 6

mass of useful product formed/theoretical mass x100

Question 7

what can the percentage yield of a product be used to investigate?

Answer 7

efficiency of practical techniques

Question 8

define atom economy

Answer 8

the percentage of reactants that are made into useful products

Question 9

how do you calculate atom economy

Answer 9

Mr of desired products/Mr of the sum of reactants x100

Question 10

what can atom economy of a reaction be used investigate

Answer 10

efficiency of using a specific reaction to produce a product

Question 11

write the ideal gas equation

Answer 11

PV=nRT
pressure Pa, volume in m3, temperature in K, R=8.31

Question 12

what are the standard conditions?

Answer 12

298K
100kPa

Question 13

how do you convert between Kelvin and Celcius temperatures

Answer 13

C to K= +273
K to C= -273

Question 14

define empirical formula

Answer 14

simplest whole number ratio of elements/atoms in a compound

Question 15

what equation links moles, concentration and volume?

Answer 15

Concentration= moles/volume