Content Page
All test tube reactions and observations 2
Periodicity 7
Shapes of Molecules 8
Formulas 9
Chemical equations from each topic 11
All past paper equations 15
Thermodynamic definitions 19
Organic Mechanisms and pathways 20
Time of Flight 25
Bond strength 26
Required Practicals 27
1
, AQA A Level Chemistry - All Test-tube reactions (Inorganic and Organic)
Species: ion/ Test Positive Result Equation
Functional
Group
SO42– 1. Acidify White precipitate of SO42– (aq) + Ba2+ (aq) ⟶
with dilute BaSO4 BaSO4 (s)
HCl
2. Add BaCl
CO32– Add dilute HCl Effervescence 2 HCl + CO32–⟶ CO2(g) +
Gas produced turns H20(l) + 2Cl–
limewater cloudy
OH– Damp red litmus Turns from red to blue N/A
paper
Halide Cl– 1. Acidify White precipitate Ag+ (aq) + Cl– (aq) ⟶
ion with dilute dissolves in dilute NH3 AgCl(s)
HNO3 2. Add
Br– AgNO3 Cream precipitate Ag+ (aq) + I– (aq) ⟶ AgI(s)
3. (Add dilute dissolves in conc. NH3
NH3 (NOT with dilute)
followed
I– by conc. Yellow precipitate Ag+ (aq) + Br– (aq) ⟶
NH3) Insoluble in conc. NH3 AgBr (s)
Mg2+ In separate With OH–: white Mg2+ + 2NaOH ⟶
test-tubes: precipitate Mg(OH)2 + 2Na
• Add dilute With SO42–: No visible
NaOH change Mg2+ + SO42– ⟶ MgSO4
• Add dilute
H2SO4
Ca2+ Flame test Brick-red N/A
In separate With OH–: white Ca2+ + 2NaOH ⟶ Ca(OH)2
test-tubes: precipitate/ + 2Na
• Add dilute suspension
NaOH With SO42–: slight white Ca2+ + SO42– ⟶ CaSO4
• Add dilute precipitate
H2SO4
Sr2+ Flame Test Red N/A
2
, In separate With OH–: No visible Sr2+ + 2NaOH ⟶ Sr(OH)2
test-tubes: change + 2Na
• Add dilute With SO42–: white
NaOH precipitate Sr2+ + SO42– ⟶ SrSO4
• Add dilute
H2SO4
Ba2+ Flame Test Green N/A
In separate With OH–: No visible Ba2+ + 2NaOH ⟶ Ba(OH)2
test-tubes: change + 2Na
• Add dilute With SO42–: white
NaOH precipitate Ba2+ + SO42– ⟶ BaSO4
• Add dilute
H2SO4
NH4+ 1. Add NaOH Litmus paper will turn NaOH + NH4+ ⟶ Na+ +
2. Heat sample from red to blue. NH3 + H2O
3. Hold damp
red litmus
paper at
test tube
mouth
Cu2+ Add dilute NaOH Pale blue precipitate [Cu(H2O)6 ]2+ (aq) + 2OH–
Aqua ion (aq) ⟶ [Cu(H2O)4(OH)2]
[Cu(H2O)6] (s) + 2H2O (l)
2+
(pale
blue Add excess NaOH No visible change N/A
solution)
Add dilute NH3 Pale blue precipitate [Cu(H2O)6 ]2+ (aq) + 2NH3
(aq) ⟶ [Cu(H2O)4(OH)2]
(s) + 2NH4+
Add conc. NH3 Deep blue solution [Cu(OH)2 (H2O)4] + 4NH3
⟶ [Cu(NH3)4(H2O)2 ]2+ +
2H2O + 2OH–
Add Na2CO3 Green-blue precipitate [Cu(H2O)6 ]2+ + CO32– ⟶
CuCO3 + 6H2O
Add conc. HCl Green solution [Cu(H2O)6 ]2+ + 4Cl– ⟶
3