# Scince

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am having trouble with Restate the problem in terms of the following:
Manipulated variable
Constant (control) variables
Principles of experimental design
State in correct form the hypothesis you intend to demonstrate.
I have conducted the experiment but I am not sure how to properly give there answers.

The experiment was How do leaves change color?

I collected 2 large leaves from a maple and acorn tree. I chopped the leaves into very small pieces and put them into small jars labeled with the name or location of the tree.
I added rubbing alcohol to each jar to cover the leaves.
I covered the jars loosely with aluminum foil and place them into a tray containing 1 inch of hot tap water.

I waited an hour stiring each jar gently about every five minutes. I hand to kepp the water at a good temp. and replaced it twice when ti became to cold. I cut a long thin strip of coffee filter paper for each of the jars and label it.
I removed the jars from water and uncovered. I placed a strip of filter paper into each jar so that one end is in the alcohol. The colored alcohol traveled up the paper to reveal different shades of green, yellow, orange and red.

• Scince - ,

I am not certain you tested a hypothesis, you did a demonstration. What was it you tested?

• Scince - ,

My Hypothesis was the I beleive leaves change color due to photosynthisis.

• Scince - ,

You are not testing "Hypothesis was the I beleive leaves change color due to photosynthisis". To test this you would need to have two samples of leaves from the same tree one of which you allow to continue to photosynthesise and one you stop.
An alternative at this time of year and used in some schools is to have leaves from an evergreen oak and from a deciduous oak. The latter are red/brown. The chromotography test then shows the difference between the two.

• Scince - ,

so basicllly I have to change my experiment or add more to it. The leaves are still grren here so there are plenty of trees to pick from. I guess I can let on brown and cover another with foil. would this work as an experiment?