All chemistry equations to memorise

Sterilisation of water

Sterilisation of water

Cl2(g) + H2O(l) ⇌ HCl(aq) + HClO (aq) (as HClO kills bacteria)

Reaction of Cl with water in sunlight

2Cl2(g) + 2H2O(l) ⇌ 4HCl(aq) +O2(g) (chlorine is rapidly lost so musts constantly be supplied)

Solid Cl compound added to water instead of gas

NaClO (s) + H2O ⇌HClO(aq) + Na+(aq) +OH-(aq)

Reaction of Cl2 with NaOH

Cl2(G) + 2NaOH(aq) → NaClO(aq) + NaCl(aq) + H2O(l) (reaction involved in synthesis of bleach)

Decomposition of sodium hydrogencarbonate

2NaHCO3(s) → Na2CO3(s) +H2O(l) +CO2(g)

Reaction of Cl2 with NaOH

3Cl2(aq) + 6NaOH → 5NaCl + NaClO3 +3H2O

Reaction of Mg with steam

mg(s) +H2O(g) → MgO +H2 (reacts vigorously)

Reaction of Mg with H2O(l)

Mg(s) + H2O(l) → Mg(OH)2(aq) +H2(g)

Reaction of Ca with H2O(l)

Ca(s) + H2O(l) → Ca(OH)2(aq) +H2(g)

Reaction of Sr with H2O(l)

Sr(s) + H2O(l) → Sr(OH)2(s) +H2(g)

Reaction of Ba with H2O(l)

Ba(s) + H2O(l) → Ba(OH)2(s) +H2(g)

How is Mg used to extract Ti?

TiO2(s) +2C(s) +2Cl2(g) → TiCl4(l) +2CO(g), TiCl4(l) +2Mg(s) →Ti(s) + 2MgCl2(s)

Reaction of Cl- with H2SO4

NaCl + H2SO4 →NaHSO4 +HCl

Reactions of Br- with H2SO4

NaBr + H2SO4 →NaHSO4 +HBr, 2HBr + H2SO4 → SO2 +2H2O +Br2

Reactions of I- with H2SO4

NaI + H2SO4 → NaHSO4 + HI, 2HI + H2SO4 → I2 +SO2 + 2H2O, 6HI + H2SO4 → 3I2 + S + 4H2O, 8HI + H2SO4 → 4I2 + H2S + 4H2O

Reactions inside a catalytic converter

2CO +2NO → 2CO2 +N2, C8H18 +25NO →12.5N2 + 8CO2 + 9H2O

Haber Process

N2 +3H2 ⇌ 2NH3

Reactions in a Lithium cell

Li+ +CoO2 +e- → LiCoO2, Li+ +e- → Li Overall: Li +CoO2 →Li+(CoO2)-

Reactions in a Fuel cell

2H2(g) + 4OH-(aq) → 4H2O(l) +4e-, O2(g) +2H2O(l) +4e- → 4OH-(aq) Overall: 2H2 + O2(g) → 2H2O(l)

Free radical substitutions

Cl2 → 2Cl●, CH3CH3 + CL● → ●CH2CH3 + HCl, ●CH2CH3 +Cl2 →CH3CH2Cl + ●Cl,●Cl +●Cl → Cl2

Ozone depletion

Cl● + O3 → CLO● +O2, ClO● + O3 → 2O2 + Cl●

Formation of biodiesel

Triglyceride + 3CH3OH →(NaOH) 3 fatty acids (methyl esters) + glycerol

Reaction of sodium with water

2Na(s) + 2H2O(l) → 2NaOH(aq) + H2O(g)

Reaction of sodium with oxygen

4Na(s) +O2(g) →2Na2O(s)

Reaction of magnesium with oxygen

2Mg(s) +O2(g) → 2MgO(s)

Reaction of aluminum with oxygen

4Al(s) + 3O2(g) →2Al2O3(s)

Reaction of silicon with oxygen

Si(s) + O2(g) → SiO2(s)

Reaction of phosphorus with oxygen

4P(s) +SO2(g) →P4O10(s)

Reaction of sulphur with oxygen

S(s) +O2(g) →SO2(g)

Reaction of sodium oxide with water

Na2O(s) + H2O → 2NaOH (alkaline solution)

Reaction of magnesium oxide with water

MgO(s) + H2O(l) → Mg(OH)2(aq) (weak alkaline solution)

Reaction of phosphorus oxide with water

P4O10(s) + H2O(l) → H3PO4(aq) (strong acid)

Reaction of sulphur dioxide with water

SO2 (g) + H2O(l) → H2SO3 (aq) (strong acid)

Reaction of sulphur trioxide with water

SO3(g) + H2O(l) → H2SO4(aq) (strong acid)

Reaction of sodium oxide with HCl

Na2O(s) +2HCl → 2NaCl + H2O

Reaction of Magnesium oxide with HCl

MgO(s) + 2HCl (aq) → MgCl2 +H2O (used to neutralise XS stomach acid)

Reaction of magnesium hydroxide with HCl

Mg(OH)2(s) + 2HCl(aq) → MgCl2 (aq) +2H2O (used to neutralise XS stomach acid)

Reaction of aluminium oxide with H2SO4

Al2O3(s) + 3H2SO4(aq) → Al2(SO4)3 + 3H2O

Reaction of aluminium oxide with NaOH

Al2O3 + 2NaOH + 3H2O(l) → 2NaAl(OH)4 (white precipitate)

Reaction of silicon oxide with NaoH

SiO2(s) +2NaOH(aq) → Na2SiO3(aq) + H2O(l)

Reaction phosphorus oxide with NaOH

P4O10(s) + 12NaOH → 4Na3PO4 + 6H2O(l)

Reaction of sulphurdioxide with NaOH

SO2(g) + 2NaOH(aq) → Na2SO3 + H2O(l)

Reaction of sulphurtrioxide with NaOH

SO3(g) + 2NaOH(aq) → Na2SO4(aq) + H2O

Redox titration half equation of MNO4-

MnO4-(aq) + 8H+(aq) + 5e- → Mn2+(aq) + 4H2O(aq)

Redox titration half equation of Cr2O72-

Cr2O7- + 14H+ + 6e- → 2Cr3+ + 7H2O

Contact Process

1) V2O5 + SO2 —> V2O4 +SO3

2) V2O4 + ½ O2 —> V2O5 (vanadium oxide used as catalyst for manufacture of sulphuric acid)

Iron acting as a catalyst

S2O82- + 2Fe2+ → 2SO42- + 2Fe3+ , 2I- + 2Fe3+ → I2 + 2Fe2+

Reaction of Mg with O2

2Mg(s) + O2(g) → 2MgO(s)

Reaction of Ca with O2

2Ca(s) + O2(g) → 2CaO(s)

Reaction of Sr with O2 (to form strontium(II)oxide)

2Sr(s) + O2(g) → 2SrO(s)

Reaction of Sr with O2 (to form strontium(IV) oxide

Sr(s) + O2(g) → SrO2(s)

Reaction of Ba with O2 (to form Ba(II) oxide)

2Ba(s) + O2(g) → 2BaO(s)

Reaction of Ba with O2 (to form Ba(IV) oxide)

Ba(s) + O2(g) → BaO2(s)

Reaction of Mg with HCl

Mg + 2HCl → MgCl2 + H2

Reaction of Ca with HCl

Ca + 2HCl → CaCl2 +H2

Reaction of Sr with HCl

Sr + 2HCl →SrCl2 + H2

Reaction of Ba with HCl

Ba + 2HCl → BaCl2 + H2

Reaction of Mg with H2SO4

Mg + H2SO4 → MgSO4 +H2

Reaction of Ca with H2SO4

Ca + H2SO4 → CaSO4 +H2

Reaction of Sr with H2SO4

Sr + H2SO4 → SrSO4 +H2

Reaction of Ba with H2SO4

Ba + H2SO4 → BaSO4 +H2

Reaction of calcium oxide with water

CaO + H2O → Ca(OH)2

Reaction of strontium oxide with water

SrO + H2O → Sr(OH)2

Reaction of bariumoxide with water

BaO + H2O → Ba(OH)2

General equation for carbonate + HCl

Carbonate + dilute HCl → chlorine + water + carbondioxide

General equation for carbonate and H2SO4

Carbonate + dilute H2SO4 → sulphate + water + CO2

General equation fro hydroxide + HCl

Hydroxide + dilute HCl → chloride + water

General equation for hydroxide + H2SO4

Hydroxide + dilute H2SO4 →sulphate + water

General equation for oxide + HCl

Oxide + dilute HCl → Chloride + water

General equation for oxide + H2SO4

Oxide + dilute H2SO4 → sulphate + water

General equation for oxide + water

Oxide + water → hydroxide

Complete ligand substitution of cobalt hexaaqua complex with NH3

[Co(H2O)6]2+ (aq) + 6NH3 (aq) → [Co(NH3)6]2+(aq) + 6H2O(l) pink → yellow

Partial ligand substitution of cobalt hexaaqua complex with OH-

[Co(H2O)6]2+ (aq) + 2OH-(aq) → Co(H2O)4(OH)2 + 2H2O(l) pink → blue ppt

Partial ligand substitution of copper hexaaqua complex with OH-

[Cu(H2O)6]2+ + 2OH- → Cu(OH)2(H2O)4 (s) + 2H2O blue ppt → light blue ppt

Partial ligand substitution of Cu(OH)2(H2O)4

Cu(OH)2(H2O)4 + 4NH3 → [Cu(NH3)4(H2O)2]2+ + 2H2O + 2OH- light blue ppt → deep blue solution

Complete ligand substitution of copper hexaaqua complex with Cl-

[Cu(H2O)6]2+ +4Cl- → [CuCl4]2- + H2O blue → yellow

Complete ligand substitution of cobalt hexaaqua complex with Cl-

Co(H2O)6]2+ +4Cl- → [CoCl4]2- + H2O pink → blue

Formation of NO2+

HNO3 +H2SO4 —> NO2+ + H3O+ + 2HSO4

Reaction in alkaline hydrogen oxygen fuel cell

1) 2H2O + 2e- → 2OH- +H2

2) O2 +2H2O +4e- —> OH-

Reaction of aluminum oxide with base

Al2O3 + 2OH- + 3H2O —> 2Al(OH)4-

Reaction of aluminum oxide with acid

Al2O3 + 6H+ —> 2Al3+ + 3H2O

Autocatalysis

Product of the reaction catalyses the reaction

Iron acting as a catalyst during the Haber Process