Investigating osmosis

Explain the movement of water molecules during osmosis.

Hint: look for the definition YOU wrote.

An investigation was carried out into how the concentration of sugar solution a piece of potato was placed in affected the mass of the potato.

In experiment A the concentration of sugar solution is higher than the concentration inside the potato cells.

Which direction will the net movement of water be in?

• Into the potato

• No net movement

• Out of the potato

So what do you think will happen to the mass of the potato when the concentration of sugar solution is higher than the concentration inside the potato cells?

• Increase

• Stay the same

• Decrease

What do you think will happen to the mass of the potato when:

b) The concentration of sugar solution is lower than the concentration inside the potato cells?

• Increase

• Stay the same

• Decrease

Explain why the mass of the potato increases when the concentration of sugar solution is lower than the concentration inside the potato cells.

What do you think will happen to the mass of the potato when:

c) The concentration of sugar solution is the same as the concentration inside the cell?

• Increase

• Stay the same

• Decrease

Why did the students measure the mass at the beginning and the end of the experiment?

Why were the potato pieces dried before weighing them a second time?

Look at the picture of the experimental set up above.

What was controlled in this investigation?