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

Estimate magnitude field-radius-outer radius, A toroid having a square cros...

A toroid having a square cross-section, 5.48cm on the side, and an inner radius of 19.4cm 450 turns and carries a current of 1.04A. (It is made up of a square solenoid instead of r

What are harmful effects of noise, Harmful effects of Noise: 1. Noise c...

Harmful effects of Noise: 1. Noise causes nervous tension, aggression and commotion in normal human beings. 2. Continuous noise damage hearing power and complete deafness.

How many pounds does one gallon of water weigh, How many pounds does one ga...

How many pounds does one gallon of water weigh One wine calculates or US gallon of water weighs 8.34 pounds. An Imperial Gallon is ten pounds of water at 62F and 30 inches of

Mass as a measure of the amount of inertia, Mass as a Measure of the Amount...

Mass as a Measure of the Amount of Inertia: All objects resist alters in their state of motion because they have inertia. However some objects have more of a tendency to resist

Describe how optical fibers used as hydrophones, Describe how optical fiber...

Describe how optical fibers used as hydrophones. Optical fibers are employed as hydrophones for sonar and seismic applications. Each hydrophone systems along with more than one

Describe kirchoffs voltage law, Describe Kirchoff's Voltage Law? Ans. I...

Describe Kirchoff's Voltage Law? Ans. It describe, " the sum of the Voltage drops around a DC series circuit same to the applied voltage or source. E = E 1 + E 2 = E 3 .

Define the density of lead, A fishing line's lead sinker has a volume of 1....

A fishing line's lead sinker has a volume of 1.40 x 10 -5 m 3 . The density of lead is 1.2 x 10 4 kg/m 3 . What is the apparent weight of the sinker when immersed in freshwat

Explain basic principle of holography, Explain basic principle of holograph...

Explain basic principle of holography Holography is a new method of producing a 3D image of a 3Dobject. An ordinary photograph is only a 2D image of a 3D object. The photograph

Demonstrate ultrasonic flaw detector in its reflection modes, Demonstrate t...

Demonstrate the typical ultrasonic flaw detector in its reflection modes? A typical ultrasonic flaw detector into its reflection modes is as demonstrated below: Assume

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