Basic principles of spectrophotometry, Physics

Basic principles of spectrophotometry:

An absorbance spectrophotometer is an instrument that measures the fraction of the incident light transmitted through a solution.  In other words, it is used to measure the amount of light that passes through a sample material and, by comparison to the initial intensity of light reaching the sample, they indirectly measure the amount of light absorbed by that sample.

Spectrophotometers are designed to transmit light of narrow wavelength ranges (see Figure 1 the electromagnetic spectrum).  A given compound will not absorb all wavelengths equally-that's why things are different colors (some compounds absorb only wavelengths outside of the visible light spectrum, and that's why there are colorless solutions like water).  Because different compounds absorb light at different wavelengths, a spectrophotometer can be used to distinguish compounds by analyzing the pattern of wavelengths absorbed by a given sample.  Additionally, the amount of light absorbed is directly proportional to the concentration of absorbing compounds in that sample, so a spectrophotometer can also be used to determine concentrations of compounds in solution. Finally, because particles in suspension will scatter light (thus preventing it from reaching the light detector), spectrophotometers may also be used to estimate the number of cells in suspension.

We will be using a spectrophotometer several times this semester to quantify the concentration of chemicals present in a solution.

 

 

Posted Date: 10/15/2012 5:40:15 AM | Location : United States







Related Discussions:- Basic principles of spectrophotometry, Assignment Help, Ask Question on Basic principles of spectrophotometry, Get Answer, Expert's Help, Basic principles of spectrophotometry Discussions

Write discussion on Basic principles of spectrophotometry
Your posts are moderated
Related Questions
Shockley, Brattain and Bardeen won a Nobel Prize for what small invention? Ans: Shockley, Bardeen and Brattain won a Nobel Prize for small invention of transistor.


A pure semiconductor is known as intrinsic semiconductor. It has thermally formed current carriers (i)  They have four electrons in the outer part of orbit of atom and atoms are

how to write a program from this using c language

Write down the Maxwell's electromagnetic wave equations both in differential form.

Voltage: Voltage is the electrical equivalent of mechanical potential. If a person drops a rock from the first storey of a building, the velocity it will reach when dropped wi

Kinematic chain related to an assembly of rigid bodies connected by joints that is the mathematical model for a mechanical system. As in the familiar use of the word chain, the rig

What do you mean by pure spectrum? What is an impure spectrum?

Advantages of induction motors 1. Simple design. 2. Low cost compared to other motors of the similar capacity. 3. High overload capacity. 4. Very rugged construction.

Work: In its technical sense, work is the product of force and distance, and work is done only when a force causes movement.  We can see this by the formula: Work = Force x