Today, the O section learned about half-life, and the downsides of technology. First, they signed up for an account with www.explorelearning.com, which was pretty easy to do. Next we attempted to do an activity on half-life, which is a very good one actually, but many of them could not get the shockwave program to work. Half-life is the amount of time it takes for a radioactive element to decay to one-half of its original level. So, if it starts at 100 atoms and has 50 atoms left after 10 seconds, the half-life is 10 seconds.
In full group today, the W, L, and S section began the unit on atoms and bonding. I handed tests back from Unit 4. These were mostly disappointing for me, as too many students did not study at all on their own, relying only on what we did in class. I even posted a version of the test on my moodle site (https://moodle.l-spioneers.org/course/view.php?id=44) that had some of the same questions I asked on the test, but in most classes only one or two students took it. I will be posting the test for Unit 5 soon. Please encourage your son or daughter to take the test!
This is a hard unit. Today we talked about valence electrons (the outermost electrons around an atom with the most energy) and their role in chemical bonding. In fact, these valence electrons are THE reason why bonding happens. The atoms want to be stable, which means getting an outer shell (valence shell) of 8 electrons. They do this through borrowing or sharing electrons. The three types of bonds are ionic, covalent, and metallic. Parents, ask your child to look at their notes and go over them with them. It might help to review the book as well, making sure they understand the concepts.
We also watched a short video on gold, learning about its properties—conductivity, malleability, ductility, little reactivity, soft, dense, and easy to shape (malleable). I gave time in class to work on their homework, which was 5-1, 2, 3. It is due the next full group.
Sweet justice.
