Preparation of Potash Alum
Typically, alunite is the mineral from which potash alum is derived. But potassium alum is also made industrially these days. Adding potassium sulfate to concentrated aluminum sulfate solution is one of the most popular preparation techniques. Potassium chloride can be used instead of potassium sulfate if the sulfate has a higher iron content.
Lab Preparation of Potash Alum
The laboratory preparation of potash alum involves the following steps and materials:
Materials Required
The materials required to prepare potash alum are potassium sulfate, aluminum sulfate, sulfuric acid, and distilled water. These chemicals are weighed and dissolved in separate containers.
Procedure
The procedure for the preparation of Potash Alum is as follows:
- First, dissolve about 5g of potassium sulfate in a minimum quantity of distilled water in a beaker.
- In a separate conical flask, dissolve 50g of aluminum sulfate in warm water.
- Then about 3 ml of dilute sulfuric acid is added to make the solution clear.
- The two solutions are then mixed, and the resulting solution is filtered if unclear.
- The concentrated solution is then cooled slowly to allow the potash alum to crystallize.
Cooling and Crystallization
The solution obtained in the preparation of potash alum is cooled slowly, allowing the potash alum to crystallize. The crystals that form are collected using a vacuum pump, washed with a 50/50 ethanol-water mixture, and allowed to dry.
Determining the Yield
The mass of the potash alum crystals is determined, and the percentage yield is calculated based on the theoretical yield.
Observation
The following properties of Potash Alum were observed after its preparation:
Potash Alum |
|
---|---|
Color | Colourless |
Structure | Octahedral |
Acidic Property | Changes Blue litmus to red |
Solubility | Soluble in water |
Precautions
The safety measures that need to be taken while preparing Potash Alum in the Lab are as follows
- Wear protective gear: Put on safety goggles, a lab coat, and gloves to protect yourself from potential chemical splashes or skin contact.
- Handle chemicals carefully: When handling chemicals, always use a funnel to minimize spills and ensure proper containment of the reagents.
- Heat the mixture properly: Heat the mixture gradually and stir continuously to ensure even heating and prevent localized.
- Dispose of waste properly: Dispose of all waste materials, such as used glassware and chemical residues, according to laboratory safety procedures and local regulations.
Potash Alum
Potash Alum also known as Potassium Aluminum Sulfate is a chemical compound commonly used as potassium sulfate dodecahydrate. It has an octahedral structure in a neutral solution and changes into a cubic structure in an alkali solution. This compound is a double salt and is frequently utilized in medicine and water treatment procedures. It is often termed as ‘fitkari‘.
In this article, we will have a detailed description of the Potash Alum, properties of potash alum, uses of the potash alum, and how the potash alum is prepared.
- 258.192 g/mol (anhydrous)
- 474.37 g/mol (dodecahydrate)
IUPAC Name |
Aluminum Potassium Sulfate Dodecahydrate |
---|---|
Chemical Formula |
K2SO4.Al2(SO4)3.24H2O |
Molar Mass |
948 gm/mol |
Density |
1.725 g/cm3 |
Melting Point |
92 to 95 °C (198 to 203 °F; 365 to 368 K) |
Boiling Point |
200 °C (392 °F; 473 K) |
Table of Content
- What is Potash Alum?
- Structure of Potash Alum
- Properties of Potash Alum
- Preparation of Potash Alum
- Uses of Potash Alum