Key Equations

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Acid + active metal

Acid + Active metal → Salt + Hydrogen

eg. Hydrochloric acid + magnesium → Magnesiium chloride + hydrogen gas

2HCl(aq) + Mg(s) → MgCl2(aq) + H2(g)

All active metals are above 0.00 V (the hydrogen half cell) in the standard reduction table. Eg. Zn, Mg, Fe, etc.


Acid + Carbonate

Acid + Carbonate → Salt + Water + Carbon dioxide

Eg. Ethanoic acid acid + Sodium hydrogen carbonate → sodium ethanoate + water + carbon dioxide

CH3COOH(aq) + NaHCO3(aq) → CH3COO-Na+(aq) + H2O(l) + CO2(g)


Acid + Alkali

Acid + Alkali → Salt + Water

eg. Sulfuric acid + potassium hydroxide → potassium sulfate + water

   H2SO4(aq) + 2KOH(aq) → K2SO4(aq) + 2H2O(l)

Note: All neutralisation equations are exothermic in nature as the net ionic reaction is the same.

H+(aq) + OH-(aq) → H2O(l) ∆H < 0


9.2 Equations


Fermentation equation

C6H12O6(aq) → 2C2H5OH(aq) + 2CO2(g)


Combustion of ethanol

C2H5OH(aq) + 3O2(g) → 2CO2(g)+ 3H2O(l)


The addition of bromine to cyclohexene



The addition polymerisation of

a) polyethylene

b) polyvinyl chloride

c) polystyrene

nCH2=CH2 (-CH2-CH2-)n
ethylene polyethylene

nCH2=CHCl  (-CH2-CHCl-)n
vinyl chloride polyvinyl chloride

nCH2=CHC6H5  (-CH2-CHC6H5-)n
styrene polystyrene


Condensation of glucose to cellulose

n(C6H12O6) → (-C6H10O5-)n + (n-1)H2O(l)

glucose → celluose + water

Cellulose is made up of repeating glucose units.


Note: The beta 1,4 glycosidic bond (oxygen atom joining the monomers) alternates with the CH2OH side group


Ethanol to Ethylene and Ethylene to Ethanol


Remember the catalyst for each


Lead acid battery

Anode: Oxidation: Pb(s) + SO42-(aq) → PbSO4(s) + 2e- 0.36 V

Cathode: Reduction: PbO2(s) + 4H+(aq) + SO42-(aq) + 2e- → PbSO4(s) + 2H2O(l) 1.69 V

Electrolyte. The 4 to 6 M H2SO4 (The sulfuric acid keeps the concentration of Pb2+ ions low by forming insoluble lead sulfate, which adheres to the electrodes. Since the electrodes are intact the battery is rechargeable.)


Lithium cell

Anode: Li → Li+ + e-
Cathode: ½ I2 + e- → I-

Electrolyte: Solid sate. The non aqueous electrolyte is a conducting polymer containing Li+I- formed between the anode and the cathode.


Describe how commercial radioisotopes are produced

Include equations

Commerical radioisotope can be produced in

a) nuclear fission reactors by bombarding target nuclei with neutrons.
Eg. The production of Cobalt-60,   +  →

Nuclear fission reactors produce radioisotopes that are ‘rich’ in neutrons.


b) particle accelerators by bombarding target nuclei with charged particles(eg. protons & ions).

Eg. The production of carbon-11 in a cyclotron, + → 

Particle accelerators produce radioisotopes that are deficient in neutrons.



9.3 Equations


Acid rain formation from sulfur and nitrogen oxides
Sulfur oxides Nitrogen oxides

SO2(g) + H2O(l) ==> H2SO3(aq) Sulfurous acid

SO2(g) + ½O2(g) =particulates> SO3(g)

SO3(g) + H2O(l) ==> H2SO4(aq) Sulfuric acid

NO(g) + ½O2(g) ==> NO2(g) brown

H2O(l) + 2NO2(g) ==> HNO3(aq) + HNO2(g)

Mixture of nitric and nitrous acid


Strong and weak acids

All 0.1 M conetration

Strong acids completely ionise producing a lower pH

HCl(aq) ==> H+(aq) + Cl-(aq), pH =1

H2SO4(aq) ==> 2H+(aq) + SO42-(aq), pH = 0.7

Sulfuric acid is diprotic, producing more H+ ions than HCl and therefore has a lower pH

Weak acids only partially ionise producing a higher pH

CH3COOH(aq) <==> CH3COO-(aq) + H+(aq), pH = 3

Citric acid <==> citrate ion + H+(aq) , pH = 4 (Ionises less than acetic acid producing a higher pH)


HCO3- reaction with and acid and a base

Acting as an acid (H+ donor): HCO3-(aq) + OH-(aq) <==> CO32-(aq) + H2O(l)

Acting as a base(H+ acceptor): HCO3-(aq) + H3O+(aq) <==> H2CO3( aq) + H2O(l)


9.4 Haber process

What catalyst is used? How does it work?

N2(g) + 3H2(g) <==> 2NH3(g) ∆H = -92kJ

A finely ground iron catalyst, Fe3O4, with a large surface area, is used in the Haber process.

The gaseous nitrogen and hydrogen molecules are adsorbed and rearranged forming the ammonia molecules. By lowering the activation energy, a catalyst enables a more rapid reaction at lower temperatures.



Esterification is a condensation reaction: Alcohol + organic acid --> Ester (alkyl alknoate) + Water

When you are given the structure of an ester first identify the acidic component by circling it.


The acidic component is the last part of the ester name. eg. methanoate, ehtanoate, propanoate, butanoate, etc.

Name the following ester. What was it made from?


Answer: ethyl propanoate. Made from ethanol and propanoic acid



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