OCR A Level Chemistry Paper 1 – Physical and Inorganic Chemistry – Complete Definitions and Exam Answers

OCR A CHEMISTRY A LEVEL PAPER

1




Amount of substance equations - Answer -mass = mr x moles



mol = vol x conc



vol(gas) = mol x 24 (dm)



PV=nRT

(pressure, Pa, volume, m3, moles, -, 8.314, temp, k)



Empirical formula - Answer -The simplest whole number ratio of

atoms of each element in a compound

,Molecular formula - Answer -The number and type of atoms of each

element in a molecule



Anhydrous - Answer -Contains no water molecules



Hydrated - Answer -Crystalline compound containing water molecules



Celsius to Kelvin - Answer -K=C+273



% yield and atom economy - Answer -% yield = (actual/ theoretical) x

100



atom economy = (desired products/all reactants) x 100



Cu2+ in aq solution - Answer -[Cu(H2O)6]2+

Pale blue



Fe2+ in aq solution - Answer -[Fe(H2O)6]2+

Pale green

, Fe3+ in aq solution - Answer -[Fe(H2O)6]3+

Yellow



Mn2+ in aq solution - Answer -[Mn(H2O)6]2+

Pale pink



Cr3+ in aq solution - Answer -[Cr(H2O)6]3+

Green



Cu2+ and NaOH (aq) - Answer -Initially:

[Cu(OH)2(H2O)4] (s)

Blue precipitate



Excess:

No change



Fe2+ and NaOH (aq) - Answer -Initially:

[Fe(OH)2(H2O)4] (s)

Green precipitate