Osmosis Investigation

Osmosis Investigation

Introduction

For my Biology coursework I am investigating osmosis. I am doing a

practical to find out how osmosis affects one of the variables listed

below.

Variables

* Temperature

* Concentration of sucrose solution

* Time in solution

* Beginning mass of chip

* Amount of distilled water with the sucrose solution

* Beginning surface area of chip

Idea

I have chosen to test what effect the concentration of sucrose

solution has on the chips.

Prediction

* I think that the chips in the test tubes containing more sucrose

solution than distilled water will increase in temperature.

* I think that the chips in the test tubes containing less sucrose

solution than distilled water will decrease in mass.

* I think that the chips in the test tubes containing equal amount

of sucrose solution and distilled water will stay roughly the same

mass.

I think the graph of the results will turn out like the sketch I have

drawn below.

Page 1

Reason

Osmosis is the passage of water molecules from a region of high water

concentration, through a semi-permeable membrane to a region of low

water concentration.

Sucrose solution contains less water molecules (more dilute) than the

chip so the water molecules will pass into the sucrose solution

therefore making the mass of the chip less. Dilute water contains more

water molecules (more concentrated) than the chip so the water

molecules from the dilute water will pass into the chip therefore

making the mass of the chip more.

The more sucrose solution added to distilled water the more dilute the

solution becomes. Therefore the more sucrose solution added the

smaller the mass of the chip becomes. The more distilled water added

the more concentrated the solution becomes.