testing

Question 1

what’s the test for starch

Answer 1

Iodine:
Add a few drops top a sample, it will turn from yellow-brown to blue black

Question 2

What is the step for reducing sugars

Answer 2

Benedics
place a sample in a boiling tube and add benyboys, heat at 80 degrees for 3 mins and observe the colour change.
Blue → green →yellow → orange → red

Question 3

non reducing sugars

Answer 3

First check for reducing sugars to make sure there none

Then take a seperate sample and boil it with ccl to hydrolyse sucrose into glucose
Coll the solution and neutralise with sodium hydrogen carbonate

Re test for reducing sugars

Question 4

Lipid test

Answer 4

Lipid emulsion test

Add a sample to ethanol and mix thoroughly

Filter
Pur solution into a clean test tube
A cloudy white ppt should form

Question 5

protein test

Answer 5

bieurette
blue to lilac

Question 6

quantitative testing for reducing sugars

Answer 6

use a clolourimeter and do the benidicts test. use a centrifuge to spin out the ppt and serperate.
Use a colorimeter on a red setting to fond the transmission of light. Less light → more sugar

Question 7

Biosensors

Answer 7

They take a biological chemical variable that can not be measured and convert it into an electrical signal

Question 8

Chromatography

Answer 8

Stationary phase →the thin layer of paper or tlc plate

Mobile phase → the solvent

As the solvent travels up the paper the solute travels with it. Different components of the mixture have different levels of solubility and so are therefore more out less likely to stay mobile. This separates them

Question 9

What is RF

Answer 9

Component distance/ solvent