lab 4 - Must have Goggles! Turn in Colloidal Clay Report on...

Info iconThis preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon
Must have Goggles!!!!!!!!! Turn in Colloidal Clay Report on front desk Quiz is first put away everything but pen or pencil. Keep Quiz face down until all are finished Keep Silent until I collect quizzes Ask Question if something is unclear 20 min
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Objectives for the Spectrophotometer Locate and identify the function of the parts of a spectrophotometer Use a spectrophotometer to measure relative absorbance
Background image of page 2
Light White light is composed of all colors (prism) Measured in wavelengths λ Molecules either absorb and transmit light -the color of light transmitted is the color we see -chlorophyll- reflects green, absorbs the rest
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 4
A spectrophotometer measures the amount of light (at a specific λ) absorbed or transmitted by a sample A λ is selected, a known quantity of light is sent through the sample The machine measures: Transmittance- how much light is transmitted by the sample Absorbance- how much light is absorbed by the sample
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 6
We do this to determine the relative concentration of one substance in a solution Generally the higher the absorbance, the greater the concentration Need at least two readings from one sample over time Or one reading from two samples Absorbance is measured from 0 - 2
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The Blank test tube Contains all components of the sol’n except the substance being tested Volume should be equal to that of sample tube May have to compensate with water or buffer
Background image of page 8
Image of page 9
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 11/11/2008 for the course BIOL 111 taught by Professor Rizzo during the Fall '07 term at Texas A&M.

Page1 / 27

lab 4 - Must have Goggles! Turn in Colloidal Clay Report on...

This preview shows document pages 1 - 9. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online