Chemistry - 2008-09
North Middlesex Regional High School
Mr. Virzi
Online Lab Assignment – due Friday, Feb. 6th
Go to
http://www.explorelearning.com
and click on "Enroll in a class here." On the next screen click on "New students, please click here to continue the enrollment process." Enter the class code on the next screen - 29MMD9VBWY. Enter your name and create a password; you should be on the Chemistry page.
1. Scroll down to "Solubility and Temperature," click on "Launch Gizmo." Make two tables, one for potassium nitrate and another for salt. In each table, in one column measure how much of each solid will go into solution at 5 different temperatures. Look at the bar chart as you add your material, click on "show numerical value" - you're trying to find maximum amount of solid material that the water can hold before any solid starts to pile up at the bottom of the beaker, without overshooting. Try practicing at 9 degrees with potassium nitrate, and see if you can come up with a value of 19g as the maximum amount of potassium nitrate that dissolves at that temperature. You have to have your own 10 temperatures; copying someone else's values will get you a zero for this assignment. If you can't get this to work, PLEASE ASK ME FOR HELP.
2. Go to Triple Beam Balance Gizmo and measure the weights of the paper clips, the cone, and the light bulb.
3. Go to the Density Laboratory. (a) Find the densities of objects 1-12 and A, B & C in g/cc. EXTRA CREDIT - find the liquid density in the big container needed for the following: (b) Crown C floats, Crown B sinks, and Crown A stays suspended. (c) Suppose you had a truckload of mixed plastics consisting of materials 2, 3, 5, 11, and 12. What density liquid could you use to isolate material 11 in pure form by getting the other four materials to float? (d) What density liquid could you use to isolate material 3 in pure form by getting the other four materials to sink?
