The S section finally got to have their half group lesson on radioactivity today. This was the first day 2 I have been in school in a while, and they lost out last week when my back went out. Today, though, they learned what radioactivity is, what an alpha particle, beta particle, and gamma ray are, how it is detected (with a geiger tube and counter--at least that is one way), what causes radioactivity (a ratio of protons to neutrons that is not close to 1), and how to protect yourself from it (shielding, limiting exposure, or running away). They got the chance to see some radioactive rocks and saw a geiger tube and counter in action.
The W and O sections completed lesson 5-2 (see notes for Day 61) and did very well with the kits. The L section moved on and completed lesson 5-3, learning what covalent and metallic bonds are. A covalent bond is a sharing bond, where two atoms share their valence electron/s so that they both have a full shell of 8 (or two with hydrogen). This is different from an ionic bond--in an ionic bond, the electron is transferred, leaving each atom as an ion (a charged atom), and the charge draws them together. A metallic bond is different than both of these. For metals, the nuclei sit in a sea of electrons, which allows the metal to be very malleable, ductile, etc. without breaking like an ionic compound would.
The L's also got a chance to use the kits some more, finishing the first two pages, and making O2 among others. It is a great opportunity for seeing how the bonds create compounds, and why certain compounds exist while others don't.
Sweet justice.
