Uses of Colorimeter

The colorimeter is an instrument that allows for the measurement of light and its intensity to match the colour as it is perceived by the human eye. The colorimeter compares the measured colour against the standard colours with the colour spaces.

Table of Content

• What is Colorimeter?
• General principle of calorimeter
• Uses of Calorimeter
• FAQs

What is Colorimeter?

Colorimetry is one of the methods of spectroanalytical methods. The variation of the colour of a solution with a change in concentration of some solute component in the solution forms the basis of colorimetry.

The colour is either the inherent colour of the constituent itself or due to the formation of a coloured species by the addition of a suitable reagent. The intensity of the colour can then be compared with that obtained by treating a known amount of the chemical substance in the same manner.

General Principles of Colorimeter

A colorimeter may be used to measure the concentration of a chemical in a solution if the chemical imparts a characteristic colour to the solution.

• The colorimeter optical system isolates a narrow waveband of light at a selected absorption peak for the chemical that is measured.
• The intensity of the transmitted light at the absorption wavelength is a function of the concentration of the chemical in the solution.
• When only the light at this wavelength is used, Beer’s law is obeyed and maximum sensitivity is obtained for the instrument.
• The use of the narrow wavelength band usually makes possible the elimination of the absorption effects of other chemicals in the solution.
• However, the effect of some chemicals cannot be eliminated if they change the complex ion formation of the chemical being measured. This is the case when uranyl nitrate is measured in a solution containing nitric acid.

A more stable colorimeter can be made if the dual beam principle is utilized. This is usually accomplished by comparing the light intensity at an absorption wavelength with the intensity of a reference beam from the same light source.

List of Uses of Colorimeter

A colorimeter uses the human eye as the detector. The user compares the observed colour of the unknown sample against a standard or a series of coloured standards of known concentrations.

• Colorimeter is a small and portable device that can be used to analyze the colour contrast and the brightness on a television or computer screen, allowing the user to adjust the settings to obtain the best quality picture.
• In the printing industry, this device is a basic element in a colour management system, in addition to checking the electronic components and quality of pulp paper and measuring the quality of the printing ink.
• The colorimeter is also used by diamond merchants to measure the optical properties of precious stones.
• The instrument is also used in cosmetology to measure the sun protection factor of the products that are applied to the skin.
• These can analyse the skin tomes and tooth colour to help diagnose dermal and dental diseases.
• In real life, the hospitals use some types of these devices to test the concentration of haemoglobin in the blood. When the Hb is oxygen-rich, the blood appears red.
• A high concentration of Hb within the blood is an indicator of good health, while low levels suggest that the muscle’s internal organs and brain are not receiving a sufficient supply of oxygen.
• The colorimeter is also used to test for water quality in real life by screening for chemicals such as chlorine, fluoride, cyanide, dissolved oxygen, iron, molybdenum and hydrazine.