Science lab report on finding the boiling point of an unknown substance

Essay by frankinsonJunior High, 8th gradeA+, November 2006

download word file, 1 pages 3.0 1 reviews

Downloaded 26 times

Aim

The aim of this investigation is to identify the unknown solid.

Hypothesis:

I predict that if we can identify the unknown solid, by finding its melting point in a water bath, and match it with the periodic table.

Variable:

Amount of the unknown substance

Heat given to the water bath

Output:

Temperature of the unknown substance

Method:

Equipment:

* Bunsen burner

* Tripod

* Unknown solid

* Beaker

* Stopwatch

* Boiling tube

* Stand

* Clamp

* Thermometer

First we take some time to set up the equipment, and after checking that everything is safe, we start boiling the beaker filled with water, having a boiling tube with the unknown substance inside it. Since this is group work, and to make it fair, we take turns recording the temperature every 30 seconds or looking at the stopwatch. By changing our shifts every 5 minutes, this will make us to have a fair chance of working.

We than turned of the fire once the solid melted.

Time Temp

0:30 21

1 22

1:30 22

2 22

2:30 23

3 24

3:30 25

4 27

4:30 29

5 31

5:30 33

6 35

6:30 37

7 39

7:30 44

8 49

8:30 51

9 53

9:30 54

10 57

10:30 59

11 63

11:30 69

12 80

12:30 86

Discussion and Conclusion

I think the unknown substance is naphthalene, for it has the highest melting point, matching the data we collected. I think we have been doing well on it, without doing anything things wrong. Also we should have turned the fire down a little bit, for the temperature suddenly rised from 80 to 86 degrees.

Modifications to Original Plan:

I got an idea of doing it in turns during the setup for the investigation. Since Sam agrees in my...