Title:      Chemistry Laboratory, Observation of a Chemical Reaction                      (combustion)

Name:       Group member and roles:

Date:

Purpose:      To observe a chemical reaction (combustion reaction)

            To make quantitative and qualitative observations about a reaction.

            To record those observations

            To use a balance

            To become familiar with the term "rate of reaction."

Materials:

Note: In this experiment, you will be working with an open flame.  Tie back long hair and secure loose clothing.  Also wear safety goggles and a lab apron or coat at tall times when working in the lab.

Procedure:

1)    Note (and record) the appearance, odor, and feel of the unlighted candle.

2)    if necessary, heat the bottom of the candle and secure it to a glass       square.

3)    Zero (tare) the balance.

4)    Mass (Weigh) the candle and measure the length of the candle.

5)    Record the mass and length of the candle set-up prior to lighting the       candle.

Stop here.   Make sure 1-5 is complete prior to lighting the candle.

7)    Light the candle. 

8)    Record the time the candle was lit. 

9)    After about 5 minutes, blow out the flame and immediately place a lighted       match in the "smoke" about 2 cm above the wick.  Note and record the       result.

10)   After the candle has cooled, record the mass and length of the candle       setup.

11)   Light the candle for a second time, recording the time the candle was lit.

12)   Let the candle burn for about 5 minutes (record the time).

13)       Observe and describe the color of the flame, and any other observations.

14)   After about 5 minutes, blow out the flame (record the time).

15)   Record the mass and length of the candle.

16)   Light the candle for a third time.

17)   After about 5 minutes (record the time), blow out the flame.

18)   Record the mass and length of the flame.

Calculations:

For each trial, find:

      The change in the mass of the candle.

      The rate or the change in the mass of the candle per minute.

      The change in the length of the candle.

      The rate of change in the length of the candle per minute.

      Graph the change in the length of the candle over time for several points.

      Based on your graph, can you predict how long the candle would burn?

            What is the expected burn time of the candle?

Conclusion:

Discussion:

No MSDS for this Laboratory experiment.