Periodic Table

[chazzyj12]

What in the periodic table is a period?

[Gef]

One of the horizontal rows. The vertical columns are called groups. Ask for more info if needed.

[KebabMeister]

Was it given the name period because when it was first created they didn't know all the elements?

[Peter Pedant]

no its not a period as in an American full stop. (.)

Dobereiner noticed that some elements could be grouped in threes - his triads

and Mendeleev saw that the triads could be further ordered. And its the repeaty thing that gives the idea of a period - something that is repeated.

Schoolchildren usually do Mendeleev around the same time as they get wave functions, and so it all sort of fits together.....

[Gef]

Sorry to Peter for me being so pedantic but...

In th UK (at least) the horizontal rows are called periods. Across a period certain properties (ionisation energy for example) show a general increasing trend and then the pattern is repeated again in the next period, hence the term periodic.

In Scotland most kids learn about Mendeleev and the Periodic Table in the lower years of secondary school but the full significance of the Periodic Table is not revealed until the pre-university year - and even then not wave functions.

[Peter Pedant]

No me again

not those wave functions

v = f lambda

that type of wave thing - - it goes back to zero.

Not psi x psi star.....do you realise I am so old that the pre uni chemistry courses didnt have that sort of thing ?

I was gonna tell Chazzy that he shares his name with an important engineer - Chezy, who did stuff on open channel flows, but we got sort of side tracked......

[Gef]

LOL Peter