Reddit mentions of Chemistry, 11th Edition

There's Crash Course chemistry (YT channel). Great way to start in my opinion. I'd say watch that before moving to Khan academy. Then, if you're really serious: https://www.amazon.ca/Chemistry-Raymond-Chang/dp/0073402680 .

I learned with this book, turned out good.

> https://www.amazon.ca/Chemistry-Raymond-Chang/dp/0073402680

I think this is the book that my coworker gave to me! glad to know that this book is a good source to turn to!

Basically, all sorts of things happen because the atoms, molecules, or whatever, want to be stable, i.e to achieve lowest energy. Forming ions, i.e. removing or adding electrons to the atom, is a way for atoms to achieve lowest energy (stable).

The spdf orbitals do come into play. An atom's electronic configuration can be described with its shells, orbitals, and the number of electrons in the orbitals. For example, iron's configuration is 1s^2 2s^2 2p^6 3s^2 3p^6 3d^6 4s^2 . The electrons has another property, its spin. Spin is an intrinsic form of angular momentum, thus carries energy. Electron can spin two way (that is the up and down arrow you see in orbitals). Pauli exclusion principle says that there cannot be two electrons in a single orbital that have the same spin (since the momemtum is the same direction, it will add up and increase energy). For the similar reason, the pairings of all electrons in a degenerate orbital (i.e. 2p, 3p, 3d, etc. orbitals with the same energy) decreases the energy (cancelled out spins in a way). However, the pairing of electron also increases energy because it decreases the distance between electrons. So, the degenerate orbitals is more stable when it is half filled or fully filled (the latter is more stable). The orbital can be more stable: just don't have the orbital. The energy of an atom is lowered when a specific set of degenerate atomic orbitals is empty, fully filled, or half filled.

Now consider the iron atom again. When it ionizes, it will want to be mroe stable. An obvious option is to take off 4s orbital entirely, losing 2 electrons, thus creating Fe^2+ . Now the ion's configuration is 1s^2 2s^2 2p^6 3s^2 3p^6 3d^6 . To become more stable, we can make 3d orbitals (take ten electrons at most) half-filled to 1s^2 2s^2 2p^6 3s^2 3p^6 3d^5 . Compared to the neutral atom, the ion loses three electrons, making it Fe^3+ . But the energy difference between Fe^2+ and Fe^3+ is not that big. External energy and chemical environment can convert them to each other. For example, oxidizing agents, a category of chemicals that love to rob electrons from others, can make Fe^2+ become Fe^3+ by accepting an electron from Fe^2+ .

Are they structurally different? Yes, other than the configuration difference (I think it can count as structure), the atomic radius is different. Fe^3+ is smaller because it has fewer electrons obviously, meaning less repulision between them, and thus stronger attraction to the nucleus.

Textbooks include the one given in the sidebar by Oxtoby and Chang's one. You may be able to find these books in your local post-secondary library. The edition doesn't matter. Oxtoby is a little hard, but it is good for in depth explanation. Chang is great for AP and other high school studnets.

Those are the full names
Here are links
Zumdahl:
http://www.amazon.com/Chemistry-Steven-S-Zumdahl/dp/061852844X/ref=la_B001ILMCPG_1_2?s=books&ie=UTF8&qid=1406049265&sr=1-2
Chang:
http://www.amazon.com/gp/aw/d/0073402680?pc_redir=1405946005&robot_redir=1
Buy them used and you don't need the latest edition (This saves a lot of money)