Osmosis

Question 1

Write a method for osmosis practical.

Answer 1

1. Fill 2 beakers: one with 50cm3 distilled water another with 50cm3 concentrated sugar solution (or more for increased accuracy)
2. Cut 2 cubes of potato with equal dimensions and weigh on a scale
3. Place the cubes in each beaker and leave for 5 minutes
4. Remove the cubes and dry to remove excess water
5. Weigh using a scale
6. Calculate percentage change in mass using |EQUATION|
7. Repeat the test using the same solutions and masses of potato
8. Find an average mean to increase accuracy.

Question 2

What happens to the potatoes mass when the sugar solution has a higher sugar concentration?

Answer 2

It will decrease because water will move from an area of high water concentration (the potato) to lower water concentration (the solution) by osmosis through a partially permeable membrane.

Question 3

What will happen to the potatoes mass if it is placed in distilled water?

Answer 3

It will increase because water will move from an area of high water concentration (the distilled water) to lower water concentration (the potato) by osmosis through a partially permeable membrane.

Question 4

What can we determine from the point the rate of intake reverses (line crosses x-axis)?

Answer 4

This is the concentration of the potato