Experiments - 3We made an other experiment to measure the speed of the molecules of a solid substance that "move" in a liquid substance. We have put crystals of iodine (colour black-grey) in some tests-tube adding ethanol, then. Then the tests-tube have been closed with parafilm except one in which it had been made a hole. In an other test-tube we have put crystals of iodine with cyclohexane (the solution became fuchsia ), then we closed with parafilm. After approximately a week we have noticed that the substances were evaporated. The crystals dissolved, but very slowly the iodine propagated towards the high. After a week the colour were distributed inside the test-tubes, in homogeneous way. The test-tube with the hole was without ethanol and the crystals forms on the surfaces. In this example the solvent molecules went away....
A simulation of molecular motion
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