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

Integration, Integration Integration is an significant concept in mathe...

Integration Integration is an significant concept in mathematics and, together along with its inverse, differentiation, is one of the two major operations in calculus. Given a

Explain electric potential at a point due to a point charge, Explain electr...

Explain electric potential at a point due to a point charge. Write its SI unit. Derive an expression for the electric potential at a point outside a charged sphere.

Diode, #shockly diode equation..

#shockly diode equation..

Explain thermally liberated charge carriers, At 200.0 K, silicon has 1.89 x...

At 200.0 K, silicon has 1.89 x 10 5 thermally liberated charge carriers/cm 3 . If it is doped with 1 As atom to 3.75 million Si atoms, what is the ratio of doped carriers to t

How fast must a ring rotate, If a ring were constructed as knid of a space...

If a ring were constructed as knid of a space station. How fast must a 50.0-m-radius ring rotate to simulate Earth's gravity?

Determine the magnification produced, An object is placed at a distance of ...

An object is placed at a distance of 0.12m from a convex lens forms an image at a distance of 0.18m. Determine the magnification produced.

Explain antenna, Explain Antenna. Write a short note or Antenna. Name two p...

Explain Antenna. Write a short note or Antenna. Name two parts of antenna.

Determine the elapsed time in kinematics, Q. Determine the elapsed time in ...

Q. Determine the elapsed time in kinematics? Let S = 1 + c 2 + c 4 + ........  Then, S = 1 + c 2 (1 + c 2 + c 4 +.......... ) S = 1 + c 2 S    so, S - c 2 S = 1

Determine the frequency of the unknown tuning fork, An unknown tuning fork ...

An unknown tuning fork is sounded along w/ a tuning fork whose frequency is 256Hz and a beat frequency of 3 Hz is heard. What i the frequency of the unknown tuning fork?

Explain the reason when chemical changes, Chemical changes during: Dis...

Chemical changes during: Discharging: The current will flow from positive to negative plate in the external circuit. As current now enters by negative plate, the negative

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