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
The electric potential at a point in a consistent electric field in an evacuated region of space is 4 . 0 volts. The electric potential at a end 25 cm to the east of the first poin

Michelson Morley Experiment The Michelson-Morley experiment was performed within the year of 1887 through Albert Michelson and Edward Morley at what is presently Case Western

What are the applications of Neodymium-Yttrium-Aluminium-Garnet Laser? Applications of Neodymium-Yttrium-Aluminium-Garnet Laser: a. Used into materials processing as like we

The length of a simple pendulum is about 100cm known to have a accuracy of 1mm.Its period of oscillation is 2s determined by measuring the time for 100oscillations using a clock of

An iron wire has a cross-sectional area equal to 5.00×10-6m2. Carry out the following steps to determine the drift speed of the conduction electrons in the wire if it carries a cur

Motion of a swing Periodic Motion :  Motion that repeats itself in equal intervals of time is known as periodic motion.

Electrostatic field is caused by stationary charge, Induced field is caused by time-varying magnetic field

If two forces P & Q act at such an angle that the resultant force r=p. Then show that if P is doubled the new resultant is at right angle Q and it's value is ( 4P 2 -Q 2 ) 1/2

You are given 3 lenses l1,l2,l3 each of focal length 20 an object at 40cm in front of l1.the final real image is formed at focus i ofl3,find separation between l1,l2,l3 ? Ans) bet

2. Surface Crystallography and Epitaxy Fe thin films are grown on a single-crystal Al (100) substrate surface. The films grow with no dislocations (if they are thin enough) which