Colorimeter

Introduction:-

A colorimeter is a light-sensitive device that measures the absorbance and transmission of light by a color solution or liquid solution.

Principle:-

Based on beer’s law And Lambert’s law.

Beer’s Law:-

According to this law the amount of light that passes through the solute concentration and observed light is directly proportional to the concentration of solute.

Lambert’s Law:-

According to this law A Ray of monochromatic light passes through the absorbing medium it intensity of light decreases as the length of the absorbing surface medium decreases and Increases the absorbing surface medium then the light absorbance increases.

Requirement:-

1. Source of light
2. slit
3. Condenser lens
4. Filter
5. Cuvette
6. Photometer and photocell
7. Galvanometer

Working principle of colorimeter:-

1. Source of light:-

The light source of the colorimeter produces chromatic light in many directions in the form of light energy.

2. slit:-

Many direction chromatic light is directed in one direction towards the condenser lens.

3. Condenser lens:-

Light is condensed by the condenser lens and it directed towards the filter.

4. Filter:-

Light is passed by the filter in the form of a specific color and specific wavelength of light known as monochromatic light.

5. Cuvette:-

Color solution filled in a cuvette and cuvette fix in the site of cuvette holder and then fix the filter then fixed light is bombarded on cuvette then some light is absorbed and some light is transmitted.

6. Photometer:-

A photo meter absorbs transmittance light and changes in electrical form.

7. Galvanometer:-

The galvanometer receives electrical form light absorbs light and calculate and shows the result on the screen of the colorimeter and the result is given in the form of optical density.

Uses:-

• It is used in laboratories and hospitals to estimate biochemical samples such as Urine.
• It is used in the manufacturing of paints.
• It is used in the textile and Food Industries.
• It is used in water quality tests.
• It determines the concentration of hemoglobin in the blood

Advantage:-

• it is an expensive method that is used for quantitative analysis of colored samples easy to carry and transport.

Disadvantage:-

• Analysis of colorless compounds is not possible and does not work for IR and UV reasons.