Inquiry activities and laboratory activities can be approached by employing a simple learning cycle consisting of:
1. Pre-Lab 2. Laboratory 3. Post-Lab
a. Objectives b.Overview of laboratory or
inquiry c. Alternate
demonstration/discrepant event/inquiry session d. Safety
precautions e. Group size:
three f. Assignment to
groups: g. Roles a. Monitor b. Intervene a. Whole Class
Processing Ask each group to give a
one-minute or less description of their method. You can
expect the following methods: 2. Pushed the ice cube into
water in a graduated cylinder and then used balance to determine
mass. 3. Ice is placed in alcohol
and it will sink. As water is added and the mixture
stirred, the ice will rise. When the density of the
liquid is equal to the ice, the cube will be suspended.
Density of liquid is determined by measuring volume and
mass of a sample of the liquid. 4. Since ice sinks in
alcohol, mass is determined on a balance, then volume is
determined by using the displacement procedure in
alcohol. Have the groups analyze the results they got for
the density of the ice cube. How do their results vary?
What is the average or central tendency of the groups'
results? How does this compare with the known value of
the density of ice? b. Application c. Clean Up
The student will
devise methods to determine the density of an ice
cube.
Review with students
the laboratory that was done previously in which they
learned to use to determine the density of various
objects and substances. Students determined the density
of solid objects such as pebbles, marbles, and paper
clips. Explain that today they are going to apply their
knowledge of density to solve an inquiry problem.
Display two beakers
containing equal amounts of clear liquids so all the
students can see them. (One contains water and the other
contains alcohol.) Do not tell the students what the
liquids are, or that they are different. Ask the students
what would happen if you were to put ice cubes in each
liquid. Then place an ice cube in each beaker and ask the
students to explain the results. Students might remark
that the ice must be strange or funny. Inter-change the
ice cubes. The students might comment that the water must
be funny or strange. Lead the students to realize that
one liquid supports the ice the way water does and the
other does not. Students might guess that the first
liquid is water and the second liquid which does not
support the ice must be different than water. Ask the
students to establish a relative density scale for the
three materials, ice, water and unknown liquid. (Answer:
alcohol, ice, water) Now pose the problem: Find the
density of the ice cube. Show the students where the
materials are located that they can use to investigate
the problem.
Warn the students not
to taste the liquids or the ice cubes.
random or high, low,
average student per group.
Circulate around the
room from group to group. Remember that the most
important part of this laboratory is for the students to
devise their own method of determining the density of an
ice cube. Some groups will need encouragement. As you
visit groups ask questions but frame them so that they
will think about the information they really need to
determine density.
If you need to
intervene in a group ask them to describe what they have
done to determine the density of the ice cube, rather
than tell them how.
1. Used a metric rule
to calculate volume, and balance to determine
mass.
Have each team select
one of the following, and devise a method to determine
the density of: an elephant, a teenager, an automobile, a
flea.
Materials handler
should return materials to storage area.