AS.3 Amount Of Substance

Question 1

Mass/molar mass/mol

Answer 1

Moles (mol) = mass (g)
————-
molar mass (gmol-1)

Question 2

Gas volume (cm3) =

Answer 2

Moles (mol) x 24000

Question 3

Gas volume (dm3) =

Answer 3

Moles (mol) x 24

Question 4

Dm3 —————> cm3

Answer 4

X1000

Question 5

Cm3 ————> dm3

Answer 5

% 1000

Question 6

Concentration =

Answer 6

Mols (mol) / vol (dm3)

Question 7

Mole

Answer 7

An amount of substance equal to 6.02 x10^23

Question 8

Avagadros constant

Answer 8

6.02x10^23

Question 9

Molar mass

Answer 9

Mass of one mole of a substance (gmol-1)

Question 10

Moles and number of particles

Answer 10

Moles = number of particles
—————————-
Avogadros constant

Question 11

Ideal gas equation

Answer 11

pV=nRT

pressure = Pa
Volume = m3
R = 8.314
Temp = K (Celsius + 273)

Question 12

Percentage yield

Answer 12

(Actual/theoretical) x 100

Question 13

Percentage atom economy

Answer 13

Molar mass of desired
——————————- X 100
Molar mass of products

Question 14

Empirical formula

Answer 14

Simplest whole number ratio of atoms of each element in one molecule of a compound

Question 15

Molecular formula

Answer 15

Actual whole number ratio of atoms of each element in a compound

Question 16

Anhydrous

Answer 16

Crystalline compound that contains no water molecules

Question 17

Hydrated

Answer 17

Crystalline compound that contains water molecules

Question 18

Waters of crystallisation

Answer 18

Water molecules that are bonded into crystalline structure of a hydrated compound

Question 19

Heating to a constant mass

Answer 19

Continuous heating and reheating of a sample until a constant mass is achieved

Question 20

pH

Answer 20

• log[H+]

Question 21

Mass spectrometer

Answer 21

Ar = sum of (isotope x %)
———————————-
100