AH Chemistry - Practical Techniques

Heating to constant mass
1. The process of heating, cooling and weighing a substance until a constant mass is obtained
Why use a dessicator?
1. To absorb moisture from the air
Weigh by difference
1. Weigh accurately approximately
2. Weigh mass of container; add chemical and weigh container with chemical; work out mass of chemical
Preparation of a standard solution
1. By difference weigh known mass of substance
  1. Add to beaker
    1. Dissolve substance in deionised water and transfer to standard flask
      1. Rinse beaker and transfer rinsings to standard flask
        Make up to the mark
        Stopper and invert the flask several times
Organic
1. Recrystallisation
  1. Shows purity
2. TLC
  1. Shows purity
    1. Similar Rf values: high purity

Resource summary

	Created by Calum Mooney over 9 years ago