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 ______.
- Cohesion is an attraction between ______substances made possibleby ______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.
- Adhesion is an attraction between ______substances
also made possibleby ______bonds. (This is why paper towels can soak upwater 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 ______.