Required Practicals - Osmosis

Question 1

What is the objective of the practical? (Osmosis)

Answer 1

To investigate the effect of a range of concentrations of salt or sugar solutions on the mass of plant tissue

Question 2

What materials are needed for the osmosis practical?

Answer 2

-a potato
-a cork borer
-a ruler with mm scale
-labels or permanent marker
-paper towels
-a sharp knife or scalpel
-a top-pan balance accurate to at least 0.01g
- a range of sugar or sodium chloride solutions
-distilled water

Question 3

What control variables are there? (Osmosis Practical)

Answer 3

-Collect results from solutions of at least 5 different concentrations.
-Keep time spent in the solution the same each time
-Keep at a consistent temperature e.g. 30 degrees.

Question 4

how do you calculate percentage change in mass?

Answer 4

initial mass / final mass

Question 5

What do we do to ensure potato chips are of the same size and will work for the practical? (Osmosis)

Answer 5

-Use a cork borer to cut five potato cylinders of the same diameter
-Use a knife to trim any potato skin

Question 6

What do we do to gather results for the different concentrations? (Osmosis Practical)

Answer 6

Measure the mass or length of potato chip before and after being put into the solution

Question 7

What control variables do we have? (Osmosis Practical)

Answer 7

• Keep the same volume of concentration of sugar or salt solution (e.g. 10cm3 each time).
  -Keep the volume of distilled water the same each time.
  -The amount of time the potato chips are left in the solution for each repeat.

Question 8

What do we do to ensure the end mass isn’t affected by the experiment to make it inaccurate? (Osmosis Practical)

Answer 8

We blot them dry with paper towels to get rid of water left on the outside.