|Water is a great solvent, which means that it will dissolve
things. This is because water is a polar molecule, with positive
and negative ends. Because of this, water will dissolve other polar molecules
such as Salt (NaCl).
|Play the movie at the right. Why did the stream of water bend when
the plastic knife was placed close? What charge do you think the knife
has? Does the charge matter? How does a water molecule simulate a bar
Water flows and, therefore, can go just about anywhere.
Wherever it goes, water will carry with it the substance or substances
it has dissolved. It can also transport less desirable materials such
as pesticides and toxic chemicals. Sewer wastewater can contain disease-causing
agents. Often sewage and agricultural wastewater contain fertilizers
which upset natural ecosystems due to a dramatic increases in growth
of algae and other water plants.
Water can cause the erosion of land, destroying valuable soil resources
and clogging streams and lakes with silt. Changes made in natural river
systems by the construction of dams or removing natural wetlands upsets
ecosystems. The photograph at the right shows how dirty water can look
when it is carrying soil resources. Imagine what this would look like
if the water carried pollution instead of dirt!
- Write a letter to the editor of a local newspaper explaining why
you believe the water in your area should be kept contaminant free. Make
sure you describe what could be done to fulfill this request.
- Water Report
- Choose and study a characteristic of water
and prepare a written report on that topic.
Topics to Choose from: Surface Tension, Capillary Action, Solubility,
Phase Changes, Density
- Note: No matter which topic you choose,
you will need to learn about polarity. All of these topics are
related to polarity in some way
and must include polarity in the explanations in your paper.
- The paper will be 3/4 to one page in length.
- It will be typed
or hand-written in ink.
- You will include an outline and rough
- Your paper should reflect your outline and include:
introduction on the importance of water and what you
will write about in your paper.
- A detailed scientific explanation
of the characteristic of water you have selected.
of examples of applications (uses) of your water property
life and nature.
- A conclusion that sums up what you
have stated and learned from your
- You must list your sources in a bibliography. Remember
it is very important that you not plagiarize or copy the
information. Such work is not worth a grade.
Encyclopedia, Edition, Volume,
City of publishing: publishing
Page title (date accessed), description
of site, URL address
- Written Project Assessment:
60% content (depth and coverage)
20% clarity of explanation,
organization of information
10% outline and rough draft