I've been away from chemistry a very, very long time. Many things have changed since, and denoting iodine by $\ce{I}$ instead of the traditional $\ce{J}$ is just the least of it.

I do know that questions like this will invoke a downvote tornado, so I will delete this question, given one to three days, hoping to get some hints by the good-willing users.

Question is, what should I read to update my knowledge without having to start from zero?

Edit (to give an extreme example): at my pre-school days, electrons orbiting an atom where depicted like planets orbiting a star. This very picture was dismissed even then, but only by hand-waving arguments.

Edit2: Thank you all for all your answers. Regrettably, I can't clone myself to look at all those resources in parallel.

I had a look (and still have) at http://www.chemguide.co.uk/ , and though it mostly states what I already knew, I hit some surprises: $\ce{AlCl3}$ has covalent bounds! Never thought of it, never before read about that.

But I want to speed up. Additional question: where can I find any cheat-sheets or exam questions (+answers) so I can speedily check my current knowledge to detect what I've missed, what is new and what I simply forgot?

• Don't delete! There are many good people in meta other than me who can help you with stuff. As a set of introductory chemistry tutorials, I recommend Chemguide, which I myself found very useful. Dec 31 '15 at 19:08
• @Ϻ.Λ.Ʀ. Chemguide what? Well, I could google, but if this should be useful not just for me, a link would be great. And chem exchange is really a friendly site compared to others here around. Dec 31 '15 at 19:13
• This is Chemguide's site: chemguide.co.uk I think it's just the notes of a British teacher, and it covers many topics. There are of course other sites like chemwiki.ucdavis.edu, and others. When you wanna study about something, just Google "X's tutorial" and you'll find many useful sites. Dec 31 '15 at 19:18
• OK, I found chemguide.co.uk , haven't had time to look into it yet, but thank you a lot for the link, and a whole lot more for caring. Dec 31 '15 at 19:19
• Also there's a similar discussion: meta.chemistry.stackexchange.com/questions/603/… Dec 31 '15 at 19:20
• @Ϻ.Λ.Ʀ. not quite unexpected, this will take me some time to read&understand. That's what I asked for, that's what I've got :-) . Dec 31 '15 at 19:44
• My best advice would be to get a good general chemistry textbook and read it.
– orthocresol Mod
Jan 1 '16 at 5:34
• Here is a list with many books: chemistry.stackexchange.com/questions/37303/… If you want to get personal recommondations I suggest you better talk in Chemistry Chat. Jan 1 '16 at 10:57
• This is almost a main-site question, isn’t it?
– Jan
Jan 2 '16 at 0:26
• @Jan I find some metas answer these kind of general questions in their own meta, not the main site. Jan 2 '16 at 12:04
• Re your edit: Dunno really, but shouldn’t that be a separate question?
– Jan
Jan 6 '16 at 16:16
• @Gyro Gearloose: You know Quantum Mechanics, I suppose (by checking your Physics SE; you know about Lorentz invariance; so I guess, you know QM:/ ); if you are well aware of QM, then start reading books like Physical Chemistry by Atkins, Paula; which is really intuitive and itself provides a base for further studies. Know about thermodynamics, chemical bonding, etcetera. Then start reading Inorganic chemistry . A systematic study would, by no means, let you to conquer the realms of chemistry, no matter by how many years you were devoid of chem-info.
– user5764
Jan 22 '16 at 3:18
• As that of Inorganic Chemistry, you can go with that of J. D. Lee ( however, it contains many typos and many mistakes). Then you can study Computational Chemistry by Errol J. Lewars to know more about Molecular Mechanics, Molecular Orbital theory, Simple Hückel theory, Hartree-Fock theory etcetera. You can decide which to skip; but these are essential to get hold of the current chemistry. Best of Luck.
– user5764
Jan 22 '16 at 3:27

I concur with @Ϻ.Λ.Ʀ. About Chemguide. It's very thorough, and has internal links to other concepts (like HyperPhysics, if you've seen that).

• Welcome to meta! Jan 3 '16 at 17:26
• Thanks! Just happy to be of help. Jan 3 '16 at 18:47

Chemical Structure & Reactivity by Keeler and Wothers is an excellent text.

It's aimed at Undergraduate courses in the UK so is fairly thorough (compared to the U.S. at least), and is more mathematical/detailed than your typically find, so if you have some prior knowledge it won't feel too dumbed down.

The chapters are fairly self-contained too, so you can dip in and out at will.

The most interesting book I've read which i feel will be good for intermediate level study is Concise inorganic chemistry by J d lee, wiley.. This book is the only book I've seen in inorganic which has so few reactions you won't believe it's an inorganic text. Buy this after you understand basic Chemistry..

P.S. For the doubt you had regarding the Covalent behaviour of AlCl3.. Every bond has some ionic and Covalent character.. It depends on polarising power of cation and polarisability of anion.. Read fajan's rules. Al3+ has high polarising power.. Thats why it's compounds are dominantly covalent.