Lab:
World’s Supply of Water
You have learned that water is cycled around the planet. As water
is cycled it passes through various forms such as, ocean water, lake water,
river water, ground water, etc. A common question asked about
water is: “What
are the proportions in which water occurs in each of its forms and settings
on earth?”
Materials:
Pipette & Medicine Droppers
Beakers
Plastic jugs that can hold several liters of water
Graduated
cylinders
A variety of smaller containers (beakers, cups, cover glasses)
Calculators
Procedure:
1. Obtain several large plastic jugs, beakers, or jars. Measure out 4
liters and pour it into these containers.
2. Imagine that the 4 liters of water represents all the world's water
supply. Using the data available on the
data sheet (Actual Percent of each type
of water) and a calculator, calculate how many milliliters of
water (out of the original 4000 ml) would
represent each form of water. For example, if you think a
particular form of water makes up 10% of
the world's water, then you would calculate that one-tenth
(10%) of the 4000 ml as follows: (4000
ml x 0.10 = 400 ml).Write your answers in the column labeled
“Actual Amount”.
3. Measuring very carefully; distribute these amounts of water into a
variety of smaller containers. Use
pieces of paper to label what form of water
is being represented by each container. Use your graduated
cylinder, pipette, and/or
medicine dropper to make precise measurements.
(NOTE -> It might be useful to know
that 1 ml = approx 25 drops /OR TO PUT IT ANOTHER WAY/
1 drop = approx. .04
ml.)
4. When you are finished, show your containers and your calculations to
the teacher. |