Project on preparation of potash alum from aluminium scrap observation table?

Answer 1

PREPARATION OF POTASH ALUM [(K2SO4.Al2(SO4)3.24(H2O)

Aim:

To prepare a pure sample of potash alum. [K2SO4.Al2(SO4)3.24H2O]

Principle:

Potash alum is prepared by dissolving an equi molar mixture

of aluminum sulphate and potassium sulphate in minimum

amount of water containing a little amount of sulphuric acid

and then subjecting the solution to crystallisation; octahedral

crystals of potash alum separate out.

Apparatus required:

Beaker (100 ml)

Trough

Funnel

Wire gauze

Conical flask (100mL)

Glass rod

Tripod stand

Chemicals required:

Aluminium sulphate: 10 g

Ethanol : 20 mL

Potassium sulphate : 2.5 g

Dilute sulphuric acid : 1 mL

Procedure:

a.Take 20 ml of distilled water in a 100 ml beaker and heat it

to about 40°c. Add about 1 ml of dilute sulphuric acid ,

warm this and dissolve 10 g of aluminum sulphate adding

small amounts at a time.

b.Weigh 2.5 g of powdered potassium sulphate (given in the

packet) and add it to the above solution stir well.

c. Heat the solution with constant stirring till potassium

sulphate dissolves completely on a water bath. Test the

solution at regular intervals of time far crystallisation point.

d.Allow the solution to cool to room temperature.

e.On cooling, white crystals of potash alum separate out.

f. Decant the mother liquor carefully and shake gently with a

mixture of (1 cc alcohol + 1 cc water) to the

crystals mixture.

g. Filter the crystals, dry these between the folds of a filter

paper and note the yield.

Results:

Weight of crystals obtained = ..................... g

Colour of the crystals = ......................

The crystals of potash alum are octahedral in shape.

Precautions:

a. Cool the solution slowly to get good crystals. Avoid rapid cooling.

b. Do not disturb the solution while cooling.

Answer 2

| Observation Table for Preparation of Potash Alum from Aluminium Scrap |

[table to include:

1. Initial weight of aluminium scrap
2. Appearance of aluminium scrap before reaction
3. Observations during reaction (e.g., bubbling, color change)
4. Final weight of aluminium after reaction
5. Appearance of final product (potash alum)
6. Purity/color of potash alum obtained
7. Yield obtained from the reaction (weight of potash alum obtained compared to theoretical yield)]

This observation table will help document the key aspects of the process and outcomes of preparing potash alum from aluminium scrap.

Answer 3

pooja nagpal