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

Illustrate briefly the significance of entropy, Illustrate briefly the sign...

Illustrate briefly the significance of entropy? Determine the work done when 2 mole of an ideal gas expands isothermally and reversible from 10 atm. To 2 atm. Pressure at 27 0 C

Action and reaction in pushing forces, Action and reaction in pushing force...

Action and reaction in pushing forces Forces work in pairs. If you push against a wall, the wall pushes with equivalent force back against you. Secure two kitchen spring balanc

Projectile motion, write all equationes of projectile motion used in calcul...

write all equationes of projectile motion used in calculation of vertical and horizontal motion

Kinematics, A particle has initial velocity 5 m/s due east and acceleration...

A particle has initial velocity 5 m/s due east and acceleration 2 m/s^2 due west. Find the distance traveled during 3rd second of the motion.

Unit and Dimensions, Physics is one of the types of science. Science works ...

Physics is one of the types of science. Science works according to scientific method . The scientific method accepts only logic, reason, and experimental evidence to tell betw

Elasticity, a mild steel wire of length 1mand cross sectional area 0./10^2 ...

a mild steel wire of length 1mand cross sectional area 0./10^2 cm^2 is stretched. within the elastic limit horizontally between two pillars. a mass of 100g is suspended from the mi

When a body is said to be in rest, REST: A body is said to be at rest i...

REST: A body is said to be at rest if it does not alter its position with respect to its surroundings.

Explain the electric forces and fields, Explain the Electric Forces and Fie...

Explain the Electric Forces and Fields This can be thought of in terms of an electric field, E, similar to the gravitational field discussed earlier [Fg = m g( r ) where at the

Lenzs law, Lenz's law (H.F. Lenz; 1835): An induced electric current a...

Lenz's law (H.F. Lenz; 1835): An induced electric current always pass in such direction that it opposes the change generating it.

Determine the view factor, Consider a horizontal cylinder with diameter D a...

Consider a horizontal cylinder with diameter D and length L. The center of the cylinder is a distance a above the ground. A wall with length W and height H is located to the side o

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