Question

There are four sketches below. The first sketch shows a sample of Substance X. The three sketches underneath it show three different changes to the sample.
You must decide whether each of these changes is possible. If a change is possible, you must also decide whether it is a physical change or a chemical change.
Each sketch is drawn as if the sample were under a microscope so powerful that individual atoms could be seen. Also, you should assume that you can see the
entire sample, and that the sample is in a sealed box, so that no matter can enter or leave.
Sample of Substance X
oli
Change 1
Change 2
Change 3
Change 1 is:
Impossible
a physical change
Change 2 is:
Impossible
a physical change
Change 3 is
Impossible
a physical change
Explanation
Check

Answer 1

Physical change: a new substance is not produced.

Chemical change: produces a new substance.

The substance x has one white dot, two black dots and one white again.

W - B - B - W.

If we look at the change 1 we can see that we have one green, two black and another green.

Is it possible to have one green atom? What does that mean? It means that we have another atom there. The problem says that the sample is in a sealed box, so that no matter can enter or leave. So in my opinion the first one is impossible.

In the second change I can't decide between physical and chemical. I think it is a chemical change because there is a rearrengement.

In the third change there are 12 molecules, Each molecule has two black atoms and 4 white atoms. In the substance x only had 24 white atoms, but in the change 3 we have 48 white atoms. As we said before the sample is in a sealed box, so that no matter can enter or leave. So it also impossible.