h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Entry: Ions - A673940
Author: Hell - U171578

Maybe there are some parts that could be formulated better... But it could have a go.

HELL

Nice one,

Now I've a request to make (please feel free to tell me to get stuffed as it may completely unbalance your article...)

I'm currently writing an entry on the properties of radiowaves and part of the entry will deal with the effect the ionosphere has on radiowaves.. .

any chance of a paragraph on the ionosphere so that I don't have to do the work in my article explaining all about it?

(Ok, I know, I'm a lazy so and so

whisky

Hmmm... Maybe you can leave the Ionosphere out, and I leave it out too, and someone else writes an entry about the Ionosphere?

Lazy too...

HELL

Oh well, you can't blame me for trying

'For an atom or a molecule to get charged it will have to either lose one electron or get one electron (or also a proton for that matter, but that's more complicated and only happens rarely). In any case the atom will become an ion and the process of losing or gaining charge is called ionisation.'

No - not quite there. What about Mg^2+? Better would be:

'For an atom or a molecule to get charged it will have to either lose or gain at least one electron (or also a proton for that matter, but that's more complicated and only happens rarely). In any case the atom will become an ion and the process of losing or gaining charge is called ionisation.'

Also, explain the relation to groups in the Periodic Table in the formation of single compounds - ie react Alkaline Metals with Halogens (NaCl, KI, etc.) - this should also explain why certain ions are +, 2+, -, 2- etc, and about the GCSEism of outer shell completion.

Have you explained that an electron is e-? The negative charge being something that exists can be hard to grasp at first...

Whoami?

Two quick questions. How do you pronounce cation? In ionisers, which produce negatively charged ions, why do we feel better? I gather that after a thunderstorm the air is filled with negative ions also, as well as standing by a waterfall.

Typo - signlalling > signalling

cation is said like ion - cashun would make no sense...

Does a brief bit on redox chemistry and the mighty OIL RIG acronym deserve inclusion here maybe?

vp

Oxidation Is Losing electrons, Reduction Is Gaining electrons! I remembered it! Wahey. Thanks, vp, you helped me revise for gcse chemistry!

Glad to be of assistance Whoami - I am now 3 months away from completing the fifth and final year of my chemistry degree, and I _still_ find it useful to write OIL RIG down at the top of the page in electrochemistry tutorials, just to straighten the basics out in my head before worrying about the complicated stuff

Well, that seems sensible. It looks like I'm not going to be a scientist - (Chem only to A2), but chemistry is easily my best subject. Thanks for the revision help!

Whoami?

I'll enter the periodic table and the 'at least' and the pronounciation of cat-ion and mention electrons being '-'.

Redox: Topic for itself. Can of worms. Different entry.

Thanks everybody for the feedback. Doing it ASAP.

HELL

OK... Now the reply:

I have added the 'at least' bit, but I I were being pedantic that wouldn't be correct: First electrons get in and out of the shells one by one (this is a quantum mechanical thing), so in the case of Mg2, at the moment it's lost one electron it is already an ion: Mg1. When it loses the other one it becomes Mg2 but then it's an Ion becoming a doubly charged ion... Just pedantry. I agree the 'at least' sound better.

"The relation to groups in the Periodic Table in the formation of single compounds..." It is linked to already, so not much explanation needed here: cf. electron shells and orbitals entry

"Have you explained that an electron is e-?" Yes. The cloud of negatively charged electrons. Was in there already.

OK?

HELL

OK. The reason it's better not to go to that level of losing one electron then another is because the intermediate phase isn't stable and doesn't exist for any serious amount of time - so it isn't of practical use.

The other two points seem clear enough. Good work!

Whoami?

Well... right...sort-of... but I wouldn't say it's not stable. There ARE enough examples of compounds which contain Mg(1) at least formal. And even Na(-1). Some of these are even of practical use.

Anyways, that charge stuff is a formality. Mg(II) is not really Mg(2+) because it is solvated in water, so... you see... the edges are blurry. But for the sake of simplicity I think that the form you suggested is easier to follow.

HELL

Yes - the stuff I say will be simple - I'm 16 and studying GCSE dual award. It's not really challenging stuff. Better to go with simpler material and then state that there are some exceptions, perhaps linking to 'Lies, Damned Lies and Science Lessons'.

solvated? d'you mean dissolved or something?

Whoami?

What the heck is GCSE?

Solvated: The Mg(2+) ions dissolved in water are surrounded by H2O molecules, and the free electrons of the 'O' are pointing to the Mg2+ ('cos basically opposites attract, y'know?) That gives ENERGY, and such a Mg2+(H2O)n complex is 'solvated Mg in water'. In the end the charge of that Mg2+ gets reduced effectively quite a bit, because all the water pointing to it is shielding the positive charge...

Anyhow, that's not the kind of stuff that really matters for common everyday-life reasoning.

HELL

I understand, I think. . GCSE is the standard terminal assessment that all UK students essentially take some variant upon. Dual award is a system where all three sciences (B,C,P) are taught to gain 2 GCSE grades - so using less time in a busy timetable. I am aiming for the top grade, which is A*A*.

Whoami?

Ta. Good luck.

HELL

Thanks! Chemistry A-Level is another 2-year course to 18, and that's when you then apply for uni. Looks like I'll be doing English or History...

Whoami?