Cal: Let’s talk about some of the elements on the periodic table, shall we?
Mrs Roberts: So, here I have an empty pop can. This is made of aluminium. Aluminium is an element. Now, each element has a chemical symbol made of one or two letters.
Cal: Right, OK. And what is the chemical symbol for aluminium?
Mrs Roberts: So, the chemical symbol is Al. See if you can see it in the periodic table.
Cal: OK. It is. It’s on the right hand side. It’s right there. Magic.
OK, well I might have been able to find that, but I’m still a little bit lost on what all of this actually means. So how has the periodic table been put together?
Mrs Roberts: Well, the modern periodic table shows us all of the elements arranged in rows, which are called periods. It has changed a lot over the years as we’ve learned more and more about atoms. The way we arrange them is in the order of increasing atomic number.
Cal: And what about these vertical columns? I mean, what does all of that mean?
Mrs Roberts: Well, elements that have similar properties to each other are put into vertical columns called groups. Now, the table is called the periodic table because the elements with similar properties occur at regular intervals.
Cal: Ah, OK. Now that does make a bit more sense.
