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

Derive the relation at spherical surface concave, Derive the mathematical r...

Derive the mathematical relation connecting n,u,v and R for refraction at a spherical surface concave towards a point object in a denser medium.

Phase difference between voltage and current in this circuit, The power fac...

The power factor of an a.c. circuit is 0.5. What will be the phase difference among voltage and current in this circuit?

Evaluate the magnitude and direction of the total momentum, Two arrows are ...

Two arrows are fired horizontally with the same speed of25.0 m/s. Each arrow has a mass of0.116 kg. One is fired due east and the other due south. Find the magnitude and direction

Obtain relativistic expression for the kinetic energy, Obtain Relativistic ...

Obtain Relativistic expression for the kinetic energy of the particle. Derive mass energy relation. Show that total energy E and momentum P are related, where m is rest mass and

Define heat engine, Define Heat engine Heat engine is a device by which...

Define Heat engine Heat engine is a device by which a system is made to undergo a cyclic process that results in conversion of heat into work. It is explained as the ratio o

Hookes law, Hooke's law (R. Hooke): The stress applied on any solid is...

Hooke's law (R. Hooke): The stress applied on any solid is proportional to the strain it generates in the elastic limit for that solid. The constant of that proportionality is

What is the maximum mass for which the blocks remain at rest, A block of ma...

A block of mass m 1 sits on a rough table. The coe?cient of static and kinetic friction between the mass and the table are s and k, respectively. Another mass m 2 is suspended

Write the relation for the force acting on a charge, Write the relation for...

Write the relation for the force acting on a charge carrier q moving with a velocity by a magnetic field in vector notation. Using this relation, reduce the conditions under which

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