Biology
2-2 Properties of Water
nAME: _____________________
pERIOD: ___________________
The Water Molecule
dATE: _____________________
The Water Molecule
Like all_________________, a water molecule is _______________.
The Water Molecule
Why are water molecules _______________?
The Water Molecule
Polarity
an _______________ atom, with ____ protons in its nucleus, has a much stronger attraction for
___________________ than does the hydrogen atom with a single _________________.
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Thus, there is a greater ___________________ of finding the shared __________________ near the
oxygen atom rather than near the _____________________ atom.
The Water Molecule
As a result, the _____________ end of the molecule has a slight _________________ charge and the
___________________ end has a slight ____________________ charge.
A _______________ molecule is _______________ because there is an uneven distribution of
_________________ between the oxygen and hydrogen _____________.
The Water Molecule
The Water Molecule
Hydrogen Bonds
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Because of their partial _________________ and ______________ charges, _____________
molecules can _________________ each other.
The Water Molecule
The attraction between the __________________ atoms on one ___________________ and the
oxygen __________ on another water _________________ is an example of a _________________
bond.
__________________ bonds are _________ as ____________ as covalent or ionic bonds.
The Water Molecule
A single ______________ molecule may be involved in as many as ______________ hydrogen
___________ at a time.
Water’s _______________ to form ________________ hydrogen bonds is responsible for many of its
______________ ____________________.
The Water Molecule
________________ bonds form between _______________ molecules.
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The Water Molecule
__________________ is an ________________ between molecules of the _____________
substance.
Because of __________________ bonding, water is extremely _________________.
The Water Molecule
Water's _________________ causes molecules on the __________________ of water to be drawn
________________, which is why _____________ of water form ___________ on a smooth surface.
_______________ also explains why some _____________ and spiders can walk on a
_________________ surface.
The Water Molecule
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____________________ is an __________________ between molecules of
_______________________ substances.
The surface of ________________ in a ________________ cylinder dips in the center because
________________ between ____________ molecules and _____________ molecules is stronger
than ______________ between _______________ molecules.
The Water Molecule
__________________ between ______________ and ____________ causes water to ______________
in a narrow tube against the force of __________________.
This effect is called __________________ __________________.
The Water Molecule
__________________ ______________ is one of the _______________ that draw water out of the
_______________ of a plant and up into its ______________ and ______________.
__________________ holds the column of ________________ together as it rises.
Solutions and Suspensions
A ___________________ is a material composed of ________ or more elements or compounds
that are ____________________ mixed but not _____________________ combined.
Solutions and Suspensions
Two types of _________________ can be made with _______________
1.
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2.
Solutions and Suspensions
Solutions
All the components of a ____________________ are evenly ___________________ throughout the
solution.
In a salt–water solution, table salt is the ___________________ —the substance that is
__________________.
Water is the ___________________ —the substance in which the _________________ dissolves.
Solutions and Suspensions
When a _____________________ of table salt is placed in warm _______________,
_________________ and ________________ ions are attracted to the ________________ water
molecules.
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Solutions and Suspensions
______________ break away from the crystal and are __________________ by ________________
molecules.
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Solutions and Suspensions
The ions gradually become dispersed in the water, forming a solution.
Solutions and Suspensions
Water's _________________ gives it the ability to ______________ both ______________
compounds and other _______________ molecules, such as _________________.
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_____________ is the greatest _______________ on Earth.
Solutions and Suspensions
Suspensions
Some materials do not _________________ when placed in ______________ but
__________________ into pieces so small that they do _______ settle out.
Solutions and Suspensions
The movement of _____________ molecules keeps the small particles _________________.
Such mixtures of _____________ and ____________________ material are known as
____________________.
Solutions and Suspensions
Some of the most important ___________________ fluids are both ___________________ and
____________________.
The ______________ that circulates through your body is mostly _________________, which
contains many _________________ compounds.
Blood also contains ________________ and other ____________________ particles that remain in
_____________________ as the blood moves through the body.
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Acids, Bases, and pH
What are ____________ solutions? What are ____________solutions?
Acids, Bases, and pH
A _____________ molecule can react to form ____________________ and
____________________________ ions.
Water is _____________ because the number of positive ____________________ions (H+) produced
is equal to the number of negative _____________________ ions (OH-) produced.
Acids, Bases, and pH
The pH scale
Chemists devised a ________________________ system called the _______ scale to indicate the
concentration of _______ ions in solution.
The ___________ scale ranges from ____ to ____.
Acids, Bases, and pH
At a pH of____, the _______________________ of H+ ions and OH- ions is equal.
Pure ___________ has a pH of ______.
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Acids, Bases, and pH
Solutions with a pH below ______ are called _______________ because they have more _____ ions
than ______ ions.
The lower the ______, the greater the______________.
Acids, Bases, and pH
Solutions with a pH above _______ are called __________ because they have more ______ ions than
______ ions.
The higher the ______, the more _____________ the solution.
Acids, Bases, and pH
Acids
An __________ is any compound that forms _____ ions in solution.
Acidic ________________ contain ____________ concentrations of H+ ___________than pure water
and have pH values __________7.
Acids, Bases, and pH
Strong ___________tend to have ______ values that range from ___ to ____.
The ________________________acid produced by the _________________to help digest food is a
____________ acid.
Acids, Bases, and pH
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Bases
A __________ is a compound that produces _______________ions (OH- ions) in solution.
____________, or_________________, solutions contain _____________concentrations of H+ ions
than pure water and have _______ values _________7.
Acids, Bases, and pH
Strong ___________, such as lye, tend to have ____values ranging from ____ to ____.
Acids, Bases, and pH
Buffers
The pH of the fluids within most ___________ in the ___________ body must generally be kept
between _____ and _____.
If the pH is _________ or __________, it will affect the chemical ___________________ that take
place within the cells.
Acids, Bases, and pH
Controlling ______ is important for maintaining __________________.
One of the ways that the body controls pH is through dissolved compounds called ____________.
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______________ are weak _________ or bases that can react with _______________ acids or
__________to prevent sharp, sudden changes in pH.
qUIZ
1.
A molecule in which the charges are unevenly distributed is
called a:
a. polar molecule.
b. cohesive molecule.
c. hydrogen molecule.
d. covalent molecule.
2.
A dissolved substance is called a
a. solvent.
b. solution.
c. solute.
d. suspension.
3.
A compound that produces hydroxide ions in solution is called
a(an):
a. base.
b. buffer.
c. acid.
d. salt.
4.
Hydrogen bonds between water molecules result from
a. adhesion between water molecules.
b. magnetic attractions between water molecules.
c. uneven electron distribution in each water molecule.
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d. ionic bonds in the water molecule.
5.
On a pH scale, a value of 2 means that the solution has
a. equal concentrations of H+ and OH- ions.
b. the same concentration of H+ ions as pure water.
c. higher concentration of H+ than in pure water.
d. lower concentration of H+ than in pure water.
END OF SECTION
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