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What is the colour of a leaf when the chlorophyll is removed?
As we know, chlorophyll is what causes the leaf to appear green. From what I know there is a very specific way to extract chlorophyll from leaves. 1. Boil the leaf to kill the cells and arrest all the chemical activity, this also makes it permeable to alcohol and iodine later on. 2. Submerge the leaf in alcohol (ethanol) which is kept in test tube. 3. Put the test tube into the boiling beaker in step one so the alcohol is boiled alone with the leaf in it. The chlorophyll should be extracted as the alcohol turn green. As for the leafs, they usually only appears lighter than it is originally is, which is VERY light green. I have never seen a leaf with absolutely no chlorophyll so can't tell you right here. WARNING: Alcohol in gas form is highly flammable.
What is the result of the Test for the presence of starch in a leaf?
Method Half fill a beaker with boiling water and add a large test tube that is a quarter full of ethanol. Allow the ethanol to come to the boil. Do not heat the ethanol in a Bunsen burner flame. This is not safe because ethanol is highly flammable. Take a leaf that has been sitting in good light for at least a few days, and soften on the boiling water for ten seconds or so. Then add to the ethanol and allow to boil for about a minute until all the colour disappears from the leaf. Remove the leaf from the ethanol. Put it back in the hot water to soften for 10 seconds. Spread the leaf out on a white tile and use the iodine solution to test for starch A blue-black colour indicates starch is present. This experiment can be repeated with leaves that have been left in the dark. or have been deprived of carbon dioxide.
What could you look for in a coleus leaf to determine if photosynthesis is occurring?
boil it in water then put it in ethanol then put iodine on it the leave will tiurn dark if photosynth is occurring
Why was the leaf placed in alcohol?
So people wouldnt leaf it at the bar haha
What color does the clear alcohol become once the leaf is boiled in it?
It really depends on the type of leaf and the color of the leaf.
What happen when leaf boil in alcohol what the alcoholl remove from the leaf?
Boiling a leaf in alcohol removes its chlorophyll, so the leaf loses its green colour.
Test for starch in a leave by photosynthesis?
Test for Starch 1. Heat some water to boiling point in a beaker then turn out the Bunsen flame. 2. Use forceps to dip a leaf in the hot water for about 30 seconds. This kills the cytoplasm, dentures the enzymes and makes the leaf more permeable to iodine solution. 3. Push the leaf to the bottom of a test tube and cover it with alcohol (ethanol). Place the tube in the hot water. The alcohol will boil and dissolve out most of the chlorophyll. This makes colour changes with iodine easier to see. 4. Pour the green alcohol into a spare beaker, remove the leaf and dip it once into the hot water to soften it. 5. Spread the decolourized leaf flat on a white tile and drop iodine solution onto it. The parts containing starch will turn blue; parts without starch will stain brown or yellow with iodine
Why do you put leaf in boil water for a few minutes?
To brew you drink. The hot water releases chemicals in the leaf.
Why was the leaf placed in alcohol after being in boiling water?
The leaf was placed in alcohol wafter being placed in the boiling water to extract the green pigment from the leaf.
Why did leaf had to be boiled in ethanol when testing leaf for starch?
Ethanol dissolves chlorophyll hence further phtosynthetic activity is stopped in the abscence of light and the leaf becomes transparent (colorless). the colorless leaf takes better stain with iodene while testing for the presence of starch.
What is the colour of a leaf when the chlorophyll is removed?
As we know, chlorophyll is what causes the leaf to appear green. From what I know there is a very specific way to extract chlorophyll from leaves. 1. Boil the leaf to kill the cells and arrest all the chemical activity, this also makes it permeable to alcohol and iodine later on. 2. Submerge the leaf in alcohol (ethanol) which is kept in test tube. 3. Put the test tube into the boiling beaker in step one so the alcohol is boiled alone with the leaf in it. The chlorophyll should be extracted as the alcohol turn green. As for the leafs, they usually only appears lighter than it is originally is, which is VERY light green. I have never seen a leaf with absolutely no chlorophyll so can't tell you right here. WARNING: Alcohol in gas form is highly flammable.
When water is used to wash off alcohol from a leaf why does the leaf turns dry?
Because the oxygen in water and peroxide in alcohol mix and tiny bubbles form and when they pop air comes out that makes the leaf dry
What is the result of the Test for the presence of starch in a leaf?
Method Half fill a beaker with boiling water and add a large test tube that is a quarter full of ethanol. Allow the ethanol to come to the boil. Do not heat the ethanol in a Bunsen burner flame. This is not safe because ethanol is highly flammable. Take a leaf that has been sitting in good light for at least a few days, and soften on the boiling water for ten seconds or so. Then add to the ethanol and allow to boil for about a minute until all the colour disappears from the leaf. Remove the leaf from the ethanol. Put it back in the hot water to soften for 10 seconds. Spread the leaf out on a white tile and use the iodine solution to test for starch A blue-black colour indicates starch is present. This experiment can be repeated with leaves that have been left in the dark. or have been deprived of carbon dioxide.
How do you carry out to test for presence of starch?
Half fill a beaker with boiling water and add a large test tube that is a quarter full of ethanol. Allow the ethanol to come to a boil. Do not heat the ethanol in a Bunsen burner flame. This is not safe because ethanol is highly flammable. Take a leaf that has been sitting in good light for at least a few days, and soften in the boiling water for ten seconds or so. Then add to the ethanol, and allow to boil for about a minute until all the color disappears from the leaf. Remove the leaf from the ethanol. Put it back in the hot water to soften for 10 seconds. Spread the leaf out on a white tile and use the iodine solution to test for starch a blue-black color indicates starch is present.
Why did the alcohol turned green when the leaf was put into it?
Alcohol is a solvent: It dissolves stuff. The leaf is porous, full of holes. When the leaf is placed in the alcohol, the alcohol gets into the leafs, and dissolves the pigments in the leaf, probably chlorophyll, which is green. This will turn the alcohol green.
What procedure did you use to separate plant pigments?
Place leaf in beaker and heat with Bunsen burner until water has discolored and boiled, then place leaf in test tube filled methylated spirits and place in same beaker as before with the burner turned OFF. Methylated spirits boils at around 80 degrees Celsius so when placed in heated water it will boil. This process will separate the chlorophyll (pigment) in the leaf.
What can you do to a banana leaf?
you can fashion it into a crude container for water, by folding it and perhaps using a bit of twine, which you can then use to boil water by placing it directly on ..top of glowing hot coals.
