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

Describe the operation of a transistor amplifier, Describe the operation of...

Describe the operation of a transistor amplifier in CE configuration. Ans:  Operation  of  a  Transistor  Amplifier  in  CE  configuration:    A  Common  Emitter  NPN transist

Determine the forbidden gap of silicon, For silicon the forbidden gap is ...

For silicon the forbidden gap is (A) 1.1ev. (B) 0.25ev. (C) 0.5ev. (D) 0.7ev. Ans: For silicon the forbidden gap is 1.1ev.

Magnitude of the acceleration, A car travels along a horizontal circular cu...

A car travels along a horizontal circular curved road that has a radius of 600 m. If the speed is uniformly increased at a rate of 2000 km>h2, determine the magnitude of the accele

Mechanics, to derive expreation for magnitude & direction for the resultant...

to derive expreation for magnitude & direction for the resultant which two are acting at a point

Geometry, define hyperbola please

define hyperbola please

Define circuit of rheostat, In the circuit shown in Figure, the slider S is...

In the circuit shown in Figure, the slider S is at the half-way point. (a) Calculate the p.d. across and the current flowing in the 400 Ω load resistor. (b) Is the circuit a

Problems/force-mc-rotating-two-masses.tex, A block of mass m is tied to a c...

A block of mass m is tied to a cord of length L that is pivoted at the center of a frictionless table. A second block of mass m is tied to the ?rst block also on a cord of length L

Constant negative velocity, Constant Negative Velocity Observe in which...

Constant Negative Velocity Observe in which the object below moves along with a constant velocity within the negative direction. The dot diagram displays in which each consecut

Radioactivity, law of successive diintegration

law of successive diintegration

Define q- factor, Q. Define: Q- factor. The Q factor of a series reson...

Q. Define: Q- factor. The Q factor of a series resonant circuit is described as the ratio of the voltage across a coil or capacitor to the applied voltage. That is Q = voltag

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