Basic principles of spectrophotometry, Physics

Assignment Help:

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.

 

922_Basic principles of spectrophotometry.png

 


Related Discussions:- Basic principles of spectrophotometry

Rectillinear motion, An elevator is stopped at the ground floor. It starts ...

An elevator is stopped at the ground floor. It starts moving upwards at constant acceleration for 5 seconds. It then keeps a constant speed for 35 seconds. Finally, it slows down

How are the ultrasonics deals with sound waves, How are the ultrasonics dea...

How are the ultrasonics deals with sound waves? Ultrasonics, deals along with sound waves which pass a specified point at least 20,000 times per second. As ultrasonic waves vib

Parsec, parsec: The unit of distance explained as the distance mention...

parsec: The unit of distance explained as the distance mentioned by an Earth-orbit parallax of 1 arc sec. It equals approximate 206 264 au, or about 3.086 x 10 16 m.

Velocity and acceleration, Velocity: It is common to find people confus...

Velocity: It is common to find people confusing the terms velocity and speed when describing how fast an object is moving.  The difference is that speed is a scalar quantit

Relation between potential and electric field, In an electric field rate of...

In an electric field rate of change of potential with distance is called as potential gradient. It is a vector quantity and its direction is differing to that of electric field. Po

A, what is electron

what is electron

Experiments with soap films, Some experiments with soap films Make the ...

Some experiments with soap films Make the following forms from wire. Dip the several forms in the thick soap solution and view the films. Dip the wire form with the slider i

Voltages relative to earth, Voltages relative to earth It is very commo...

Voltages relative to earth It is very common in electrical circuits to have an earth connection. This earth connection has no effect on potential differences across components

Electric field characterized by the electric potential, Question: A pro...

Question: A proton a absolutely charged elementary particle is released from rest at a point in space where the electric potential is 15 volts. Following to its release the par

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd