Draw line about 3/5 of the way down your paper Lab: Boiled Ice Purpose- Observe and record what changes energy causes water, beginning as ice. Draw line about 3/5 of the way down your paper TEACHER NOTES below Materials per group (of 3 students): 500mL pyrex beaker, ice, thermometer, hot plate, goggles, graph paper (optional), rulers (optional- for drawing lines on graphs), timer of some kind (read Notes section further down for an idea I used) As presented, this lab takes 3 days, which you can shorten or lengthen depending on your needs. Day 1: Spend 20 minutes with students setting up their papers (ppt slides 1-3), and to explain what’s going to happen tomorrow Day 2: Students do the lab: With their goggles on, get into groups with a beaker half full of ice and thermometer Set beaker on hot plate and turn on. Time is zero- take first measurement. Record temperature and state Take a temp. measurement every 2 min. thereafter and record Make a rough graph showing results. (Don’t worry how nice the data table and graph are; see Day 3…) Day 3: (try to make some sense of the chaos) Review what happened yesterday- the data collected, and rough graphs made Look together at graph on ppt slide #5 (you need to copy/paste that image in beforehand!) Assign homework: make a NICE graph on graph paper, annotated with names of states and drawings at the top; then a paragraph below Notes: Instead of handing out timers, I chose to put 1 big stopwatch on the screen for the entire class to use (http://www.online-stopwatch.com/large-stopwatch/ ); a nice side benefit in doing this is that it keeps everyone together also; we all begin and end at the same time As the ice melts into liquid then becomes a gas, have students record both states with %’s above each, estimating Notes about thermometer: It’s glass, so don’t jab it into ice (it’ll break) As students come into the room, have thermometers on ice, so they’re already at the beginning temperature, and won’t need to adjust to it To get accurate readings: the bulb of thermometer must be held in the center of water the entire 20 minute period; if they keep pulling it out in between readings, it’ll warm in air temp. and give a false reading (unless you’re using electronic) Like the idea of this lab but it’s too much trouble? Do this yourself as a demo one day in class. Can even have students take the measurements for you See notes are of remaining slides for more comments Day 1

Observe and record what changes energy causes water, beginning as ice. Lab: Boiled Ice Purpose- Observe and record what changes energy causes water, beginning as ice. Time, min. Temp. °C State 2 4 6 8 10 12 14 16 18 20 Day 1- students copy this onto their paper; tomorrow’s when they’ll do the actual lab Day 1

110 60 Temp. °C -10 still Day 1- students copy this onto their paper 5 10 15 20 Time, min. Day 1

Now go do collect your data and make a rough graph Day 2- after a brief review, get students working Day 2

Above, you need to copy/paste in the image from http://wp. cune Above, you need to copy/paste in the image from http://wp.cune.org/rachelahlers/files/2011/08/Picture-1.png (for copyright reasons I couldn’t include it) I also recommend pulling up for your students an animated version of this image at http://www.kentchemistry.com/links/Matter/HeatingCurve.htm Note that the day-minder in the lower-left corner says to show this to students on Day 3, as in, after they’ve got their data and rough graph finished. You want students to see this as confirmation of what they did. Showing it too soon (before they get results) will spoil the surprise. Day 3

Homework Re-draw your graph NICELY Annotate the graph: Write the state Drawing at top Write one paragraph below the graph, explaining it to a ten year old In the blank area to the right above I had a small version of that graph again from slide #5 for students to see as they worked on this. “Write the state” and “Drawing at top” refers on the inserted graph on slide #5 the titles that follow the line and the drawn water molecules at the top; having students include all this on theirs further reinforces what we’re trying to get them to understand regarding the states of matter I asked my students do their nice graph on graph paper, and with rulers for perfectly straight axis Day 3