Grade 9 Biology
Lab 2: Diffusion & Osmosis
Problem:
What is the effect
of the concentration of a solution on plants ?
Material: - 3
plastic cups or beakers
-
3 small pieces of potato
-
Distilled
water
-
2
spoons of salt
-
Balance
Procedure:
1.
Fill the 1st plastic cup with distilled
water, the 2nd with tap water
and the 3rd with tap water and add to it the 2 spoons of salt
(make sure that cups are filled with the same volume of
water)
2.
Measure the
mass of each piece of potato separately and place each in a cup
3.
Leave the potato pieces in the cups for 48 hours
4.
Finally , take out each piece from the cup rub with a tissue paper and then measure its
mass (record your data in the table below and complete it)
Results
|
solution |
I=Initial mass(gr.) |
F=Final mass(gr.) |
Change in mass M=F-I |
% change in mass =(M/I)x 100 |
|
Distilled water |
|
|
|
|
|
Tap water |
|
|
|
|
|
Salty water |
|
|
|
|
*** do not forget to prepare
your lab report before you come to the
lab