Lab 2B

Today, we had a lab.  It's on heating and cooling processing.  The purpose of this lab is to investigate the heating and cooling process, and to determine and compare two of them.  We did the cooling process first and here is the procedure:

1. put on safety equipment
2. decide the roll (observer or recorder), prepare table 1
3. obtain a test tube consisting of a themometer, remove the cotton plug and save it
4. put 300mL 30-35'C water in a 400 mL beaker
5. set up a ring stand, a buret clamp to hold the test tube
6. put the testube assembly into cold water
7. record the temperature every 30s
8. record when the solidification begins and ends and other observations
9. stop when the temperature reach 25'C

then, we started the heating process immediately, and the procedure is

1. change the roll
2. turn the plate on and raise the temperature to 55'C and 60'C
3. turn the hot plate to low heat when it reaches 55'C
4. record the temperature in table 1 and every 30s after that
5. readings should continue until it reaches 50'C
6. record the times when melting beings and ends. 
7. reseal the test tube assembly with the cotton plug and return all the equipment
8. qash your hands with soap and water before leaving

After the lab, we got to draw a heating and cooling curve.  The graph should probably look like this: