Atoms

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How is an atom drawn?

Atoms are drawn as circles. We known how many circles there will be by looking at what row the element is in, for example, oxygen is in row 2, so it will have 2 circles.

The nucleus will be in the middle (shown as a dot) and then the little circle around that will have 2 electrons around it.

The elements atomic number tells you how many electrons there should be altogether around the nucleus.

To work out how many electrons are on the outer circle of any element, you need to look at what group the element is in, for example, oxygen is in group 6, therefore, there will be 6 electrons.

If the element is on a different row, like row 3, there would be 3 circles, and all you would have to do is fill in the gaps. For example, Magnesium has 2 electrons on the outside and 2 on the inside, making 4 altogether, but the atomic number for Magnesium is 12 so there would have to be 8 electrons on the middle circle to make 12 electrons.

Atoms