CHEM 1020 Saint Marys University Chemical & Physical Changes Lab Worksheet

A. Heating Solids
1.Watch the following video to observe three solids being heated to
change. As you watch, pause the video as needed to observe each solid
before it is heated (shown again after each heating process); as it is heated
over the flame; and after it has been allowed to cool. Be descriptive and
include the types of observations described in the introduction: color,
texture, clarity. Then determine whether each change was chemical or
physical. Provide your reasoning.
2 Watch the following video to observe the sublimation of iodine. Again,
pause the video as needed to record descriptive observations of the iodine
before heating; while being heated; and after cooling. Classify the change
as chemical or physical and provide your reasoning.

B Mixing Solids with Hydrochloric Acid
1.Watch the following video to observe the first four solids being placed
into hydrochloric acid. Record your observations of the initial solids, and
then the solids after they have been placed in the acid. Note that some
reactions are fast and some are slow. Determine whether you are
observing a chemical change or no change. Provide your evidence and
reasoning. (Good examples of evidence are the indications of chemical
changes section of the background information, or their absence.)
2.Now, watch the following video to get the observations for the
cheeseburger in hydrochloric acid.

Name
Chemistry 1020
Chemical & Physical Changes
A. Heating Solids
Compound
Napthalene
Copper(II)
sulfate
Sucrose
Iodine
Lab 2 | 1
Initial Observation
Observation When
Heated
Observation When
Cooled
Type of
Change
Evidence/Reasoning
B. Mixing Solids with Hydrochloric Acid
Initial Observation
Solid
of Solid
Copper metal
Zinc metal
Cr-coated
paperclip
Marble
(calcium
carbonate)
Cheeseburger
Lab 2 | 2
Observation When
Mixed with HCl
Did a Chemical Change
Occur?
Evidence/Reasoning