There were two major events this week (actually, there were three). First we had the covalent bonding test with a day of review beforehand. Then, it was mole day, when we got to eat mole cookies and drink hot chocolate, listen to the mole song which drove Jackson crazy, and write an essay on hydrogen bonding and polarity. Lastly, we had the AP pre-test and the next day started the ionic and metallic bonding unit. The difference in electronegativity between hydrogen and oxygen results in the electron of hydrogen being pulled slightly towards the oxygen atom. This causes the hydrogen to have a slightly positive charge and the oxygen to have a slightly negative charge. Thus, in water, the slightly positive hydrogen's are attracted to the slightly negative oxygen's of different molecules. This attraction is called hydrogen bonding. It is not an actual bond, however, and is thus notated by a dashed line. Ionic bonding is a bond between a metal and a nonmetal in which the nonmetal takes the metals atoms and the two atoms are then attracted by the difference in charge. In metallic 'bonding', the cations are arranged in a lattice structure with all of the valence electrons being fairly free to move about the substance. This explains why metals are such good conductors of electricity.
So far, I understand this new section on ionic and metallic bonding very well. I was wondering why metals are ductile and malleable, although I think we will probably cover that very soon. I was also wondering why this section was called, "May the force be with you", as it doesn't seem relevant yet. I kind of hope it will be some pun on something we learn later, so halfway through the section I will be able to look back at it and go, 'Hah! I get this now.' I tried to be very engaged and a part of the learning process this week, despite the fact that most of this week was testing. I understood everything about this section so far, although I said that about the hybridization too and that didn't turn out so good. Anyways, I need to work on studying, especially with old material. I need to refresh my memory with everything, and in my free time (ha ha) I should do practice problems. I really didn't know about the sea of electrons, so now whenever I touch a metal I get this weird sensation of 'oh my, this is actually vibrating at speeds too fast for my comprehension, and the valence electrons are just kind of floating around all over the place...this is a bit worrying'.
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