Background: One of the Many Qualitative Observations You Made in Lab 1 Was That the Candle

LAB 2

BEHAVIOR OF SOLIDS ON WARMING

objectives #1a,b,c,d, 13

Background: One of the many qualitative observations you made in lab 1 was that the candle melted, a solid changed into a liquid. One of the questions that can be raised is, do all solids melt and if so do they all melt at the same temperature. In this lab you will be investigating the melting behavior of different solids in two different sources of heat, a candle flame and a Bunsen burner flame.

Purpose: Produce a qualitative vertical list of melting. Have easiest to melt at the top and the hardest to melt at the bottom.

Procedure

1. Using a pair of forceps insert each of the following materials into a candle flame. Write down your observations as you proceed through the list. Remember you want to eventually sort the substances by how easy they melt.

A. piece of candle wax

B. piece of sulfur

C. piece of lead foil

D. piece of iron wire

E. piece of tin foil or sheeting (note which you

used in your observations)

F. piece of aluminum foil or sheeting (note which you used in your observations)

G. piece of copper wire

H. piece of platinum wire

2. Repeat step one but use a Bunsen burner flame instead of the candle flame. Remember to set up the burner using a utility clamp, ring stand and drip catching pan as shown below and demonstrated by your teacher.

ring stand

Bunsen burner

to gas jet drip catcher

3. Now place a small piece of steel wool, which is finely divided iron, into the Bunsen burner flame. Record your observations and compare them with the observations of the iron wire in step 2.

4. Wind a piece of copper wire into a coil by winding it around a pen or pencil about 8 times, leaving a section bent at a right angle to use as a handle. (see below) Slip the wire off the pen and lower the coil into the flame of the candle. Record your observations.

copper wire

flame

candle

5. Now lower the coil into the Bunsen burner flame and record your observations. Be careful not to burn yourself, drop the coil when necessary!!!

Questions:

1. Which materials in step 1 change at a temperature that is clearly lower than the temperature reached in the candle flame?

2. Which materials in step 2 change at a temperature that is clearly lower than the temperature reached in the Bunsen burner flame?

3. How was the change in steel wool different than the iron wire in steps 1 and 2?

4. Using your observations to help you, place the different materials in a vertical list in order of increasing melting temperatures. If you cannot decide between two materials then place them together on your list.