Bio J – Basic Chemistry
Name: ___________________________
Properties of Water:
Water may seem like an everyday substance that is less than exciting to say the least, but from a
chemistry point of view, Water is extremely unique and without it, life could never had existed.
In this lab you will be exploring various traits and characteristics of water.
Directions: READ READ READ each introductory passage before trying the experiment. Be
sure to record all information clearly and concisely in the spaces provided. We will be rotating
through the stations AS A GROUP. DO NOT MOVE ON until you are told to. Some stations
take longer than others. Be patient.
Questions: Some of the questions (with stars) might need our notes to answer. We will be going
over the notes in the next day or two. You will answer these questions after the notes are
completed.
Station 1: Why is it taking so long to boil this water?!?
- In front of you there are two beakers in a heated water bath. One beaker contains oil and the
other contains water. AS A CLASS we will be measuring the change in temperatures in
both beakers over time.
- Step 1: When you arrive at this station begin by copying all data from previous groups into
your data chart. (Early groups, we’ll fill in your chart at the end of the lab)
- Step 2: HOLD the color coded thermometers into their color coded beaker and take the
temperature. Do not let go of the thermometer while they are in the beakers. After you are
done, remove the thermometers and place them on the table.
- Step 3: Record the current time and the temp of each beaker on BOTH your lab sheet AND
the class data sheet present at the station.
Time
Temp. Beaker - Oil
Temp. Beaker - Water
- You will eventually be graphing this data so take the rest of your time at this station to answer
the following:
What is the dependent variable?
What is the independent variable?
What will your X axis label and units be?
What will your Y axis label and units be?
What would a good title be for this graph?
Bio J – Basic Chemistry
Name: ___________________________
Station 2: Out darn spot, out I say!!! (dissolving substance)
-
-
Water is knows as a universal solvent, meaning that it is very good at dissolving many things.
But can it dissolve everything?
Step 1: Record the substances in your data chart and make predictions about whether or not
each substance will dissolve in water. This is only graded on if you did it, so no need to go
back and “correct” any predictions.
Step 2: Fill tubes to the halfway mark with water.
Step3: Add a very small amount each substance to the properly labeled tube.
Step 4: Gently swirl the test tubes or cover and invert the tubes to mix.
Step 5: Start observing your tubes. Give some time for things to settle/dissolve (not
everything is instant!)
Step 6: Record your data in your chart
Step 7: Rinse your tubes out thoroughly in the sink and return them to your station
Substance
Prediction
(will it dissolve or not)
Result
(did it dissolve or not)
Station 3: Phases of matter
All matter can exist in three phases: Solid, liquid and gas. Many substances need a little extra
help to reach one of those phases, however. In other words, for some solids to reach their
gaseous state, they need to be heated to extremely high temperatures that do not exist naturally
here on earth. Likewise for some liquids to become solids, they need to be exposed to
unnaturally cold temperatures. Water is unique in that it is the only substance that can exist in all
three states naturally on Earth: Ice, water and water vapor. Once again, this experiment will
require a class set of data, but don’t worry; you won’t be graphing anything with this one!
Step 1: The first group at this station will measure out 400mL of water in the graduated cylinder
and add to it, four ice cubes. Then record the time, and the volume of water and ice in the
cylinder. Observe how the ice cubes are floating. Do any stick up above the water? How far?
Record your data in the chart below and on the class data sheet at the station.
Step 2: Remaining groups will record the volume of the water in the cylinder AND describe the
ice (how many cubes visible, degree of melting, ice above water, how far above, etc,). Record
all data below and on the class data sheet at the station.
Step 3: If you arrive at the station and the ice cube has melted completely, just record the total
volume of the water on both your chart and the class data chart.
Bio J – Basic Chemistry
Name: ___________________________
Change in water volume as an ice cube melts
Time
Volume of
Water (mL)
Observations
Station 4: Can you walk on water?
So obviously, the answer to the question above is “no.” Although it is fun to watch people try!
But, believe it or not, there are some creatures who can walk on water. Do they have special
swimmies build into their feet? No… but they do clearly demonstrate another neat property of
water.
Step 1: Hold a clean, dry paperclip by the sides so that it is flat (use forceps for this!) and gently
try to place the paperclip right on top of the water so that it floats. Do not try dropping it on the
water or put the clip in at an angle. It must be flat and placed gently!
Step 2: Use a fresh paper clip and repeat step 1 on the second dish which contains alcohol. Did
you have the same success?
Step 3: Use the appropriate (watch the color coding!) forceps to remove the paper clips and
place them in the “used paper clip” beaker.
Describe your results below:
Station 5: Can water climb?
In middle school you probably learned the word meniscus. You probably remember that it
refers to the U-shaped appearance of the level of water when it is in a graduated cylinder. But,
do you know why that happens? Does it happen with all liquids? Let’s see!
Step 1: This station is mostly about observations. For each of the cylinders in front of you,
sketch the approximate shape of the meniscus on your paper. Use the measurements on the
cylinder to improve your accuracy. (ex: how far above the center are the edges?) Actual
volumes of liquid do not matter. Focus on the shape of the meniscus.
Bio J – Basic Chemistry
Water
Name: ___________________________
Alcohol
Oil
Station 6: From roots to leaves, how does water get there?
This station will demonstrate one of the processes that helps water make its way all the way from
the roots of a tall tree to the top. In front of you there are three glass tubes of different diameters
and a plastic straw. Use the blunt (not pointed) end of the tube if there is one. Touch the end of
the tube to the surface of the water and wait until the water stops rising. Remove the tube from
the water and hold it vertically. DO NOT LAY IT DOWN!!! Repeat with each of the other
tubes and straw. Observe the tubes and record, relative to one another, how far the water has
moved up the tube. Think about how this will relate to a plant. Record your observations below.
Now touch each tube to a piece of paper towel so that the water is pulled out of the tube. When
the tube is empty, lay it in the long white tray.
-
Rank the tubes in order according to the distance the water travelled. Start with the shortest
distance.
Bio J – Basic Chemistry
Name: ___________________________
Properties of Water Lab Discussion Questions
-
Full sentences are not required, however explanations when required must be clear and complete
Station 1: Why is it taking so long to boil this water?!?
1.
On graph paper, create a line graph of the class data. All graphing rules apply, so make sure you
look at your checklist!
2. What conclusion can you draw from your data?
3. What property of water (discussed in your notes or book) is demonstrated by your data?
Explain.
4. This property of water is quite important for us here on earth. While it may take a lot of energy
to heat up water, water also doesn’t let go of that energy and cool off very quickly. Water is
much better at storing heat than the air is. With this in mind, answer the following questions in
about a sentence each.
a. Why is the water at the Jersey shore so cold in June even when the weather is nice?
b. Why doesn’t the ocean freeze solid in the winter?
c. Would we expect Earth in general to be warmer or colder if it were covered with more
land than water?
Station 2: Out darn spot, out I say!!! (dissolving substance)
1.
What property of water makes it so good at dissolving other substances?
2. In general, what term is used to describe the group of substances that do NOT dissolve in water?
3. What characteristics must all molecules have in order for water to be attracted to them and
begin dissolving them?
4. What does the phrase “like dissolves like” mean?
Bio J – Basic Chemistry
Name: ___________________________
Station 3: Phases of matter
1.
What is unique about water when discussing the phases of matter?
2. What conclusion can you draw regarding your data from this experiment?
3. Scientists are concerned because glaciers on the north and south poles are melting. As they
melt the water is added to the oceans and in theory will increase levels of the oceans and
potentially flood land on which we live. Which of the following type of glaciers would be of
greater concern? Be sure to support your answer!
a. Glaciers on land that melt and run into the oceans (assume all melted water enters
ocean)
b. Glaciers that are already floating on the ocean and are melting directly into the ocean.
c. Both have an equal effect on the level of the ocean water
Station 4: Can you walk on water?
1.
What property is being demonstrated by the ability to float a paperclip on the surface of water?
2. What is happening with the water molecules to allow this to happen?
3. When washing dishes, water doesn’t interact with grease. Instead, water molecules stick
together and fat molecules stick together. Adding detergent breaks up the clusters of water and
the clusters of fat and allows the two to mix together. With this in mind, would you have been
able to float a paperclip on the surface of a dish of water if we had added detergent to it?
Explain.
Bio J – Basic Chemistry
Name: ___________________________
Station 5: Can water climb?
1.
What property is demonstrated by the ability of water molecules to stick to the glass?
2. Plastic is nonpolar (and uncharged). Would we have seen as clear a meniscus with the water if
we had used a plastic cylinder? Explain.
Station 6: From roots to leaves
1.
The principle in this station is called capillary action. What is the relationship between the
distance the water moves and the diameter of the tube?
2.
What significance does this have in terms of plants? Would plants want to have veins with a
large diameter or a small diameter?
3. In which of your tubes did the water just not climb at all? Consider what that tube was made of
and suggest why the water couldn’t gain any altitude?
4. Certain plants, called nonvascular plants, do not have veins and therefore can not transport
fluids long distances. What trait would you expect these plants to have in common? Do some
research and find an example of a common nonvascular plant.