Chemistry- (Analysis and Synthesis)

Metal Ion - Flame Colour

• Litihium (Li+)- Orange/ Crimson
• Sodium (Na+)- Yellow
• Potassium- Lilac
• Calcium- Red
• Barium (Ba2+)- Pale green

Anion (Negatively Charged Ion)- Test- Observation

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Carbonates- Bubbling it through limewater- CO2 gas produced

Halide- Add dilute nitric acid followed by silver nitrate- Colour Precipitate. Chloride- White. Bromide- Cream. Iodine- Yellow

Sulphate- Add dilute HCL followed by barium chloride solution- White precipitate (means original compound was a sulphate)

Metal Ion- Colour of Precipitate- Furthur tests required

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Copper Cu2+- Blue

Iron Fe3+- Reddish Brown

Iron Fe2+- Green

Magnesium Mg2+ - White

Sodium- Yellow - Insoluble in excess NaOH, red flame test

Aluminium Al3+ - White

Describe the process of carrying out a titration:

• Put 25cm3 of alkali in a conical flask with some indicator- Methyl orange. You dont want universal as it only changes colour gradually. Not as accurate
• Fill burette with 50ml of acid using funnel
• Slowly add the acid to the alkali whilst swirling
• Wait till the indicator changes colour
• Record the amount needed to neutralise the acid

• Important industrial process. Produces Ammonia (NH2) used to make fertilisers
• Nitrogen (obtained from the air) and hydrogen (obtained from natural gases)  are needed to make Ammonia

• The hydrogen reacts with nitrogen to form ammonia. Bee=cause the reaction is reversible, ammonia breaks back down into nitrogen and hydrogen,
• Higher pressures favour the forward reaction
• Higher pressues, best % yield hence 200 atmospheres
• Forward reaction is exothermic, means increasing the temprature will move the equilibrium the wrong way. 
• Greater temprature, greater yield of ammonia
• Lower tempratures, lower rate of reaction
• Iron catalyst speeds up the reaction and keeps costs down.