Finishing Up Radioactivity

We finished off the Atomic Structure and Radioactivity unit today. The unit was concluded with a unit exam composed of 36 questions. The test was very easy except for one single problem: how many alpha emissions would it take for 238/92 U to decay into 208/82 Pb. The answer was either 2,4,6,9 or none. (Please comment what you think the answer is, just curious). The test did have a rather large amount of questions over radioactive decay. I didn't mind being that I actually think radioactive decay is very interesting. Check out this link to learn more on alpha and beta decay: here. Can't wait to see what this next unit has in-store for us.