Investigating State Changes

Aim:
To observe water as it changes state from solid to liquid and then to a gas.

Equipment:
A 250 mL
beaker,
thermometer,
Bunsen burner,
heatproof mat,
tripod and gauze mat,
stopwatch,
retort stand and clamp,
ice cubes.


Method:
1. Collect enough ice so that your beaker is half full and replace the thermometer into it while you set up the rest of the equipment.
2. Set up the retort stand and clamp alongside the tripod and gauze mat.
3. Place the beaker of ice on the gauze mat and gently clamp the thermometer so that it is held upright and the scale is easy to see. The bottom of your themometer should be low enough to still be observed by water when the ice melts, but not touching the bottom of the beaker.
4. Record the initial temperature of the ice in a data table.
5. Light the Bunsen burner and start timing the stopwatch.
6. Measure and record the temperature every minute.
                                7. Continue measuring and recording the temperature until the water has been                                          boiling for 2-3 minutes.


Results:

Temp ( OC)	Time (Minutes)
5	1
6	2
12	3
17	4
26	5
40	6
60	7
78	8
92	9
106	10

Graph showing temperature change.

Discussion:
Upon setting the bunsen burner alight, the ice began to melt in the beaker. Water began to appear around the exterior of the ice, dripping down into a puddle at the bottom of the beaker.
This is because the particles in a solid (ice) are held together tightly, slightly vibrating. When these particles are heated up, the strength of their vibrations begin to increase, as they get heat energy. Eventually, their vibrations get so strong, that they push off eachother, and the ice begins to melt.

This took us around four minutes to achieve.