Comments on: Ten Tricky Elements Force a Periodic Table Upgrade

By: Matt B.

Matt B. — Tue, 21 Dec 2010 16:56:00 +0000

While they’re at it, why don’t they just put lutetium and lawrencium up next to hafnium and rutherfordium, where they belong? I think this was avoided originally because rutherfordium and elements beyond hadn’t been discovered.

By: Chris

Chris — Sun, 19 Dec 2010 23:54:36 +0000

Yet another way to confuse the undergraduates! :-)
One thing I would like to point out, since C-12 is used to define the amu, even if you had a sample of pure hydrogen (no deuterium or tritium) one mole of it would still weigh a little over a gram (1.007825 grams to be precise)

By: Andrew Moseman

Andrew Moseman — Sat, 18 Dec 2010 22:59:28 +0000

@Lee @Philip
Apologies for any confusion about that. Unfortunately it’s not easy to quickly find a table that has the atomic weights listed and is also clearly marked as being OK for commercial re-use.

By: Philip

Philip — Sat, 18 Dec 2010 22:40:27 +0000

@ Lee
Perhaps next time check the linked page before making a fool of yourself? But bad form also for the Discover sub-editor for not finding a periodic table graphic with the weights (one which had not been dumbed down to the level of morons)

By: Lee Elfenbein

Lee Elfenbein — Sat, 18 Dec 2010 18:46:16 +0000

This article says ” pull up a copy of the periodic table like this one and you’ll see TWO numbers to each element” But this not true. Right there on the chart, there is only ONE number for each element. Why? Why do you say there are two?

By: GHJ

GHJ — Sat, 18 Dec 2010 06:54:49 +0000

I never realised there was a distinction between atomic mass and atomic weight before this entry prompted me into googling it to clarify. I seem to have been misusing ‘atomic mass’ when I really meant ‘atomic weight’. So thanks for that.