Paper 1 equations

Question 1

Gas Volumes (at room temperature and pressure)

Answer 1

Moles = Volume (dm³) / 24

Question 2

Concentration of Solutions

Answer 2

Concentration (g/dm³) = Mass of solute (g) / Volume of solution (dm³)

Concentration (mol/dm³) = Moles / Volume (dm³)

Question 3

Moles & Mass Calculations

Answer 3

Moles = Mass (g) / Mr

Mr = sum of Ar of all atoms in the compound

Question 4

Titration (Higher Tier)

Answer 4

Moles = Concentration (mol/dm³) × Volume (dm³)

Question 5

Percentage Yield

Answer 5

Percentage yield = (Actual yield / Theoretical yield) × 100

Question 6

Atom Economy

Answer 6

Atom economy = (Mr of desired product / Total Mr of all products) × 100

Question 7

Bond Energy Calculations (Higher Tier)

Answer 7

Energy change (ΔH) = Total energy in (bonds broken) − Total energy out (bonds formed)

Question 8

. Number of Particles from Moles

Answer 8

Number of particles = Moles × Avogadro’s constant

Question 9

linking Mr, Avogadro’s constant, and mass

Answer 9

Mass of one particle (in g) = Mr / Avogadro’s constant