Diffusion and Osmosis
Lab Activity No. __
Diffusion and Osmosis
I. Introduction
Diffusion is the transfer of molecules (or ions) from an area of higher concentration to a lower concentration, while osmosis is the transfer of water from a higher concentration to a lower concentration. II. Objectives
1. Demonstrate diffusion and osmosis across membrane.
2. Examine the relation of membrane permeability to diffusion and osmosis.
III. Materials
2 thistle tubes, 2 big beakers, 4 tube clamps to fit iron stands, muslin cloth, cellophane, rubber bands, fine-point pentel pens, colored pencils/pens and molasses; flask, dropper, food color (any color) and rose (any color except red); 6 small cups, salt, sugar, distilled water, 4 potatoes of equal size (one is boiled), two big pieces of lettuce and raisins.
IV. Procedure
A. Molasses (one set-up per section)
Get a piece of muslin cloth enough to cover the mouth of the thistle tube and extend at least a half-inch beyond the rim. Hold the bulb up and with fingers pressed against the opening at the other end of the tube, fill the bulb with molasses syrup. Fold the edges down and fasten the muslin cloth securely around the rim with the use of the rubber bands. Fasten the thistle tube to the clamps on the iron stand with the molasses filled bulb. Fill the beaker with water and submerge the molasses-filled bulb. Prepare the second set-up using cellophane to cover the mouth of the other thistle tube. Use a fine-point pen to mark the level of the molasses in both set-ups at the start of the experiment. Study the set-ups after 24 hours.
B. Flower (rose)
Get a flask half-filled with water. Pour 8-10 drops of food color. Cut the stem of the rose with 6 inches in length. Observe after 24 hours.
C. Potato
Cut off a portion (around 1/5) of the potato, then scoop out a cavity from the other end. Stand the potato on its cut-off region inside the cup with water. Make sure that the water level is below the bottom of the
Diffusion and Osmosis
I. Introduction
Diffusion is the transfer of molecules (or ions) from an area of higher concentration to a lower concentration, while osmosis is the transfer of water from a higher concentration to a lower concentration. II. Objectives
1. Demonstrate diffusion and osmosis across membrane.
2. Examine the relation of membrane permeability to diffusion and osmosis.
III. Materials
2 thistle tubes, 2 big beakers, 4 tube clamps to fit iron stands, muslin cloth, cellophane, rubber bands, fine-point pentel pens, colored pencils/pens and molasses; flask, dropper, food color (any color) and rose (any color except red); 6 small cups, salt, sugar, distilled water, 4 potatoes of equal size (one is boiled), two big pieces of lettuce and raisins.
IV. Procedure
A. Molasses (one set-up per section)
Get a piece of muslin cloth enough to cover the mouth of the thistle tube and extend at least a half-inch beyond the rim. Hold the bulb up and with fingers pressed against the opening at the other end of the tube, fill the bulb with molasses syrup. Fold the edges down and fasten the muslin cloth securely around the rim with the use of the rubber bands. Fasten the thistle tube to the clamps on the iron stand with the molasses filled bulb. Fill the beaker with water and submerge the molasses-filled bulb. Prepare the second set-up using cellophane to cover the mouth of the other thistle tube. Use a fine-point pen to mark the level of the molasses in both set-ups at the start of the experiment. Study the set-ups after 24 hours.
B. Flower (rose)
Get a flask half-filled with water. Pour 8-10 drops of food color. Cut the stem of the rose with 6 inches in length. Observe after 24 hours.
C. Potato
Cut off a portion (around 1/5) of the potato, then scoop out a cavity from the other end. Stand the potato on its cut-off region inside the cup with water. Make sure that the water level is below the bottom of the
References: - http://answers.yahoo.com/question/index?qid=20070916052453AAjtjg1