Ms J's Chemistry Class: Rainbow Lab

Today class began with going over last night's homework on quantitative and qualitative self-observations, going over units and variables, and determining the number of neutrons.

Next, a few volunteers through the squishy whales at a bullseye. We then discussed who was the closest to the middle and who was the most consistent. This related to accuracy (how close a measurement is to the real measurement) and precision (how close a set of points are to each other) which is what we discussed first. We did some examples as a class and then tied accuracy and precision to percent error, a formula we learned last week.

We finished the notes by discussing significant digits. Significant digits are used so that our calculations are not more precise than our measurements. All digits other than zero are significant. Its the zeros that are the tricky ones. We went over the rules and then did some practice situations. We will continue to practice this next week.

We finished class by performing our first lab. This lab is entitled Mixing Solution and is a task designed to see if students can follow directions and practice good lab safety. All classes did an excellent job with the lab. If they students were precise and accurate, they should have ended with six test tubes in rainbow order with the exact same amount of water in each test tube. Not everyone achieved this, but most were pretty close. Here are some photos from the lab.