[Chemistry Class Notes] on To Prepare Colloidal Solution of Egg Albumin Pdf for Exam

We will be learning about the procedure to experiment on this page. This experiment will help us prepare a colloidal solution of egg albumin. Before getting started, let us look at what a colloid solution/mixture is in Chemistry.

Colloidal Solutions

Colloidal Solutions, known as Colloids, are mixtures where, when looked at microscopically, there is a suspension of highly tiny insoluble particles in another substance. 

We cannot assume all mixtures to be colloidal. The mixtures where suspended particles do not settle down at the bottom but still get evenly dispersed into another substance can be known as colloids.

We can Classify these Sols Into Two Different Types

• Lyophobic Sols: These are ‘liquid hating’ sols that get very little or no interaction with the dispersed phase and the dispersion medium. The dispersed phase in this sol has a slight affinity for the dispersion medium.

• Lyophilic Sols: These are the ‘liquid loving’ sols that attract solvents. Here, the colloidal solution firmly attaches to the dispersed medium and phase.

In the case of the egg albumin that is obtained from eggs, these albumins form a lyophilic sol with cold water. This sol is not affected by any traces of impurities and is stable.

Now, after learning about this concept, let us proceed with the actual procedure in theory:

Aim

The aim is to prepare a colloidal solution (lyophilic sol) of egg albumin

Theory

Lyophilic sol is obtainable from the egg albumin present in the eggs. When we mix the egg’s albumin with cold water, we obtain lyophilic sol.

This sol is stable and generally not affected by its impurities.

Egg Albumin’s formula is C₁₆H₂₆O₅.

Required Apparatus Includes

Procedure

1. The first step is to break down the outer shell of the particular egg with the help of the glass rod from our Apparatus.

2. Color the colorless liquid (albumin water) and the yellow part and decant the colorless liquid into another beaker.

3. In the beaker of 250mL, prepare 100mL of the NaCl solution of 5% (w/v).

4. Pipette on the albumin and start pouring it into the beaker that contains sodium chloride solution. Mix this by constantly stirring for 15 to 20 minutes, ensuring that the sol is prepared well and egg albumins in water forms.

5. Hence, filter the contents of the beaker with the help of filter paper, a funnel, and a label to filtrate as much as possible.

Precautions

• The Apparatus should be adequately cleaned for conducting these experiments.

• Now separate the egg albumin water and the yellow yolk before mixing it with sodium chloride solution.

• After this, we have to stir the mixture constantly in the beaker and also add the egg albumin to prepare our egg albumin sol.

• We will have to make sure that the preparation of egg albumin sol is done at room temperature because the precipitation of the egg albumin will take place in a hot solution.

• We should use distilled water to prepare the egg albumin sol. (Colloid is formed in the water when there is a presence of Egg albumin in it)

More About the Colloidal Solution of Egg Albumin

In this article, we will discuss the procedure to perform an experiment that will help us understand how to prepare a colloidal solution of Egg albumin. Before starting the experiment let’s first understand What is a colloid mixture or colloidal solution in Chemistry? 

Colloidal solutions or Colloids are the mixtures in which microscopically insoluble particles of one substance are suspended in another substance. Not all the mixtures are colloids. The mixture where suspended particles don’t settle down at the bottom but get evenly dispersed into another substance. The size of the colloids ranges from 1 nm to 1000 nm. One important class of colloidal systems is sols. In sols, the dispersed phase is a solid medium, and the dispersion medium is liquid in the state, and depending upon the nature of the interaction between the dispersed phase and dispersion medium sols can be broadly classified into two types.

Lyophilic Sols: The term lyophilic means ‘liquid-loving’ or ‘solvent- attracting’, which means in this colloidal solution there is a strong affinity towards the dispersed phase and the dispersion medium. 

Lyophobic sols: The term lyophobic means ‘liquid-hating’, which means in these sols, there is little or no interaction between the dispersed phase and the dispersion medium i.e., a dispersed phase has little affinity for dispersion medium.

Egg albumin obtained from eggs form a lyophilic sol with cold water. The sol is stable in nature and not affected by the presence of traces of impurities. Now let’s discuss the procedure.

Additional Information

• The standard method we can classify a colloid is based on the phase at which our substance disperses and our dispersion medium. Some colloids are emulsion, sol, gel, foam, and aerosol.

• Sol is a colloidal system. In this system, the dispersed phase is solid, whereas the dispersed medium is liquid—for example, Paint, Mud, Blood, Ink.

• An emulsion can be defined as a colloidal system in which the dispersion phase is liquid. The dispersion medium is also a liquid—for example, Salad Dressing, Brewed Coffee, Milk.

• Foam is another type of colloidal system where we observe that the dispersed phase is gas, and the dispersion medium is solid or liquid—for example, Whipped Cream, Bubble Bath, Fire Retardant.

• Aerosol is a colloidal system with the dispersed phase being a liquid or solid. The dispersion medium is gas—for example, Perfume, Hairspray, Mist, Fog.

• The gel is a colloidal system with a solid dispersion phase and a liquid dispersion medium—for example, Cheese, Jam, Rubber, Gelatin, Toothpaste.