Here are some topics you should know for
Chemistry Unit 3B exam.
- Test
for Halides
- Flame
tests
- Preparation
of aldehydes using simple distillation and carboxylic acids by heating
under reflux
- Preparation
of halogenoalkanes
- Test
for alkenes using bromine water and acidified potassium per manganate
- Test
for halide present in a halogenoalkane by warming with sodium hydoroxide
dissolved in ethanol followed by dilute nitric acid (to neutralize OH) and
silver nitrate followed by ammonia solution
- Distinguish
between aldehydes and ketones using Benedicts or Fehlings solution.
Formation of red precipitate confirms aldehyde
- Drawing
apparatus for simple distillation, heating under reflux and seperation of
two immiscible liquids (dropping funnel)
- Test
for sulfates, sulfites and carbonates using barium chloride solution
- Energetics:
Enthalpy of neutralisation, combustion and displacement
- Rates
of reaction
- Chemical
equilibria
- Reactions
of group 2 and group 7 elements
- Volumetric
analysis: esp thiosulfate
- Test
for SO2, CO2, H2 and O2. (by sankait36): SO2 - turns acidified potassium
dichromate(VI) from orange(Cr6+) to green(Cr3+), CO2 - turns lime water
milky (due to insoluble calcium carbonate), H2 - test with burning splint,
ignites with a pop sound, O2 - relights a glowing splint
- Uncertainties
(by sankait36): uncertainty = (maximum reading) - (minimum reading) / 2 ,
%uncertainty = (uncertainty / actual reading) * 100
- In
titration, discard the titre that is not concordant to 0.2 cm^
