ilovepdf_merged final notebook

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The Learning Goal for this assignment is: Students will learn how the interactions between
water molecules account for the unique properties of water and how the aqueous solutions form.
Take note over the following chapter. Use the Headings provided to organize your notes. Define and number all highlighted vocabulary (total 22 ) as well
as summarize and take notes over the sections. You may add pictures where needed. The pictures should be an appropriate size. Use Arial 12 for all
text. This document should be 2 pages and should be saved as a pdf before you submit it into Angel.
Chapter 15 Water and Aqueous Systems
Pages 488 - 507
15.1 Water and Its Properties
Water in the Liquid State-
Without water life would not be possible. The oxygen atoms within the water form a covalent bond
with the atoms of hydrogen. The bond between O-H is highly polar. Dipole interactions attract polar
molecules to one another. Covalent bonds are known to be stronger than hydrogen bonds. Despite
the previous statement, they are stronger than other intermolecular forces. Water has an inward force
or pull that tends to minimize the surface area of a liquid, this is called surface tension 1 . The surface
of water acts like a skin. Surface tension is reduced by a surfactant 2 which is any substance that
interferes with hydrogen bonding in water molecules
Water in the Solid State
Water in its solid state has less density than water in its liquid state. It is important for certain
organisms that ice floats, because a layer of ice on top of the water acts as an insulator for the water
beneath which stops the water from freezing solid with the exception of extreme conditions
15.2 Homogeneous Aqueous Systems
Solutions
Because of the vast amount of substances that water dissolves when they come in contact with it
you will never find water that is chemically pure in nature. All water contains dissolved substances,
and this is called an aqueous solution 3 . Within an aqueous solution the medium in which the water is
dissolved is refered to as a solvent 4 and the particles being dissolved are called a solute 5. All solutions
are homogenous mixtures. The average diameter of solute particles, which can consist of atoms ions
or molecules is ussually less than 1 nm. For this reason you can’t separate a solution through filter
paper as both the solvent and solute would pass through. Nonpolar covalent compounds do not
dissolve in water. In the process called solvation 6 , the positive and negative ions of an ionic solid
become surrounded by solvent molecules.
Electrolytes and Nonelectrolytes
An electrolyte 7 is a compound that conducts an electric current when it is an aqueous solution or in
the molten state. In order for an electric current to conduct it needs ions that are mobile, as they are
capable of carrying electrical currents through a liquid. Some ionic compounds cannot conduct an
electric current in an aqueous solution because they are insoluble, however despite this it does have
the ability to conduct in a molten state. Compounds that can’t conduct in either states (aqueous or
molten) are called nonelectrolytes 8 . In a solution that contains a strong electrolyte 9 all or almost all of
the solute exists of ions. In a solution with a weak electrolyte 10 , only a fraction of the solute exists as
ions and therefore it conducts poorly. Electrolytes are essential to all metabolic processes.