Properties of Water Notes
Chapter 2-2 (pg. 40-42)
A water molecule is made up of three atoms: 1 ___________________________ and
2 __________________. This compound makes it a very unique molecule. It is
unique because it is ____________________. Polarity means that it has an uneven
distribution of electrons between the oxygen and the hydrogens. Water is also known
as The Universal ________________________.
It has 2 major properties: _______________ and ____________________.
1. Cohesion is an attraction between _____________________ substances made
possible by _____________________ bonds. (This is why water is attracted to
itself – i.e water drops get bigger and bigger).
The property of cohesion produces a surface film on water called __________________
_____________________ which allows insects to walk on water and leaves to float on
water. Surface tension is a measure of the __________________ of the water’s
surface.
2. Adhesion is an attraction between _____________________substances
also made possible by ___________________ bonds. (This is why paper towels
can soak up water and water forms a meniscus inside of a graduated cylinder).
Adhesion and cohesion together cause a process called ___________________
_______________. This action allows water to pull other water molecules along in a
stack as it “climbs” up a structure. Example: the drawing of water out of the roots of a
plant and up into its stems and leaves..
Water has a very high specific heat which is important in living organisms for
maintaining ___________________________ in regard to internal body temperature.
Water also has a high heat of ________________________ in which water is
converted from a liquid to a gas. As water evaporates it removes __________ with it.
Example: ____________________________________________________________
Water is also _______________ _______________ as a solid than a liquid. This is
why ice floats. Water molecules ___________________ when they become solid.
A ________________________________ is any substance that dissolves other
substances.
A _________________________ is a mixture of 2 or more substances that are
dissolved by the solvent. Example: _______________________________________
A _______________________ is a material composed of 2 or more elements or
compounds that are physically mixed together but does not chemically combine. An
example would be mixing salt and pepper.
Substances that dissolve easily in water are said to be water soluble or
_______________________________ (which means ___________ ______________).
Substances that do not dissolve easily in water such as fats, oils and waxes are said to
be insoluble or _____________________________ (which means ______________
_____________________).
Acids & Bases:
One water molecule in 550 million will naturally dissociate into a hydrogen ion (H+) and
a Hydroxide ion (OH-). Chemists devised a measurement system called the pH scale
to indicate the concentration of H+ ions in solutions. This pH scale ranges from 0 to
14. Pure water has an equal number of hydrogen ions and hydroxide ions making
its pH value _____.
____________ contain higher concentrations of H+ ions than pure water and have pH
values that range from _________ to _________.
_____________ contain lower concentrations of H+ ions than pure water and have pH
values that range from ________ to _________.
__________________ are weak acids or bases that can react with strong acids or bases
to prevent sharp and sudden changes in pH which is important to maintaining
___________________________.