Science 421A
Name:
What is Water?
Use the videos “What is Water?” found on the class website to explore topics in
Chemistry, Weather and Ecology. You will need your textbook, class notes and
internet research for some problems.
Read “Water, Water Everywhere…”
Answer List the most abundant elements in the universe in order of abundance.
.
Answer List the most abundant molecules in the universe in order in order of abundance.
Watch the Video “Method and Madness” from 30:55 – 49:09 to learn more about Henry
Cavendish.
Watch and Explain Some consider Henry Cavendish to be an eccentric character, meaning that
he was unconventional and slightly strange. In a response, list the ways he was considered
eccentric and discuss if you think this characteristic could be an advantage to a scientist?
Science 421A
Research and Describe Brain Cox states that “Cavendish, like many scientists at the time, was
fabulously wealthy and so he was able to indulge his curiosity.” Today science is funded in other
ways. Research and describe how Canadian research projects in science and technology are
funded.
Observe and List Brian Cox performs an experiment that was first designed by Henry
Cavendish. When scientists publish reports they will list the materials and methods used in the
experiment design so other scientists can check their work. Complete the list of materials that
would be used in Cavendish’s report.
Materials Needed:
Observe and Record Scientists can record their observations as qualitative data under a Results
section of a report. This is data that is observed but not measured. Write your observations for
Brian Cox’s experiment.
Qualitative Results:
Science 421A
Discuss After scientists have their data they will discuss the results and analyze the evidence to
draw conclusions. In a scientific report this discussion has its own section and the scientist will
use previous scientific knowledge to analyze the results. Using pages 173-174 of the text,
discuss the results you observe for Cavendish’s chemical test.
Discussion:
State Cavendish designed another experiment to see how his newly discovered gas, hydrogen,
reacted with air. In this experiment Cavendish “created” water. In a chemical reaction what is
the term used for substances which are “created” from the reaction? (See pages 173-174)
State What does Brian Cox say “being a scientist is all about?”
Explain Henry Cavendish’s theoretical framework for how water is created was nonsense. So
the conclusions he made from his experiments were incorrect. How can he not know what is
going on but still provide a useful scientific model for water?
Explain Why do scientists publish their work?
Explain What is the difference between a book and a scientific journal?
Science 421A
Read “The History of the Exploration of Water”
Explain What did Antoine Lavoisier, one the greatest pioneering chemists, get wrong with the
building blocks of water?
Explain What component do the majority of common acids contain? (See back of your Periodic
Table)
Explain If there is a transfer of protons in acid-base reactions, what method do we use for
writing formulas for acids?
Watch the video “What is Water? Part 1” found on the class
website and Read Water: The Essential Ingredient
State What is the definition of the term ecosystem?
Answer What is the one thing that unites all life?
State During the video, it shows the percentage of water found in a crab, in human beings and in
the human brain to show how much water makes up living things. If the water is removed, what
term is used to mean the dry mass of the dry tissue in plants and animals? (See page 38 in your
textbook and “Water: The Essential Ingredient”)
Science 421A
Read “Simple but Complex”
Explain When Brian Cox uses the salt and the cup of coffee, he states that the electrons of the
hydrogen are “dragged” towards the oxygen’s electron cloud and shared. What type of bond is
he referring to? What type of compound is water?
Watch the video “What is Water? Part 2” found on the class website
Properties of Water – Polarity
Observe and Draw Brian Cox shows the polarity of water molecules by using a charged glass rod
and silk. The silk strips away electrons from the atoms in the glass rod. Given this, what is the
net charge of the rod? What is the net charge of the silk? If water bends towards the glass rod,
what side of the water molecule is interacting with the rod?
Draw Create the Lewis Dot diagram for oxygen and hydrogen.
Model and Draw We used a molecular model kit to visualize the water analogy that Professor
Cox uses to explain symmetry in your “What is Time” booklet. Use a molecular model kit to build
a water molecule and draw the structure below. Label each side with its charge. Build another
water molecule and show how two molecules would be stacked together.
Figure 1: One water molecule
Figure 2: Two water stacked molecules
Science 421A
Read “Treetops to Teardrops: The magic of Hydrogen Bonds” and use
the video “What is Water? Part 2”
Model and Draw Use a molecular model kit to build and draw the molecular compound
methane. Add the chemical formula to the Figure description.
Figure 3: Methane (
)
Explain Use your model to explain why methane is not a polar molecule in the figure
above.
Properties of Water - Cohesion and Adhesion
Water molecules are
highly cohesive (they stick
together) and adhesive
(they stick to other polar
substances) Plants take up
and transpire more water
than animals do. Xylem
raises water up to 350 feet
above the ground in some
of the largest trees on
earth.
Figure 4: Cohesion between
water molecules
and adhesion
between water
molecules and cell
walls allow water
to move up trees
Answer What gives water the property that allows it to be draw up so high within the
tree?
Science 421A
Observe and Answer Use a graduated cylinder to observe water being drawn up the glass.
Observe the dip in the water. What is this dip in the water called? Where do you properly
measure a volume of a liquid that is experiencing adhesion to the glass?
Measure and Record
Properties of Water - Solubility
Answer During the video, dissolved substances are being carried by the water in the
stream. (You can see some in the picture on the first page of the booklet) List the
substances and state if they are ionic or molecular compounds.
Review, Draw and Explain Brian Cox states that because “water molecules are small and
polar it can get in amongst other substances, like salts, and rip them apart.” Turn to
page 189 in your textbook and draw Figure 4 below. (Don’t forget to label the figure.)
Explain what is happening in the figure you’ve created.
Science 421A
State and Answer Write the chemical formula that you see in Figure 4 on page 189. Why
does Na have a +1 charge while Cl has a -1 charge?
State What is the definition of solubility?
Watch the video “What is Water? Part 3” found on the class website
The Origin of Water
Watch and Answer When Earth was forming 4.54 billion years ago, it was a molten ball
of rock. When the inner planet cooled it produced clouds from the released steam but
the planet was still hot. What property of water allowed water to remain on the planet?
Read, Think, Write. Today we can often think of extinction as a bad thing. Read “A Brief
History of Extinction” on pages 16-17 in your textbook and write an argument from the
perspective that extinction is “natural” and we shouldn’t think of it as a “bad thing”. You
must have information from the text in your argument.
Science 421A
Read, Think, Write Now write a counter argument which takes the position that
extinction can be natural but should be avoided. Use information from pages 10-13 in
your argument.
Label Use your textbook to properly label the missing processes in the water cycle.
Figure 6: The water cycle
Science 421A
Read, Think, Write Using your textbook, read about the Nitrogen and the Phosphorous
cycle and explain water’s role in each of these processes?
Nitrogen
Phosphorous
State What is the definition for nutrients?
Answer List the ions that are present in the cycles and explain why they are important for life.
Use the formulas and the charges in your answer.
Nitrogen
Phosphorous
Answer Complete all sheets on naming compounds and writing formulas. You need to know
how to do this for Grade 11 Chemistry.