Element= a substance composed of many “identical” particles called atoms. = the most basic substances that matter can be broken into by chemical means = the “ingredients” making up everything Chapter 5 – Water and Seawater What elements are in water? hydrogen (H) and oxygen (O) Information about all known elements is shown in the Periodic Table Electron (-) Proton (+) Neutron Nucleus Electron Shells The Parts of an Atom Atom = the smallest piece of an element that retains the properties of that element. Atoms contain two main parts and three types of subatomic particles Nucleus Protons Neutrons Electron Shells Electrons Figure 5.1, p. 130 Particle NameWhere FoundElectrical ChargeMass Y/N?OtherProtonNucleus+YesDetermines Type of elementNeutronNucleusøYes# can change for the same elementElectronElectron Shell-No# can change for the same element For an atom to be electrically neutral, # electrons = # protons http://www.vtaide.com/png/atom.htm Ion = an electrically charged atom. # of electrons (-) ≠ the # of protons (+) Negative ions (too many electrons) Positive ions (too few electrons) These will be attracted to each other. Oxygen O-2 Lithium Li+1 http://itc.gsw.edu/faculty/speavy/spclass/chemistry/ions.htm Compound = substance formed when two or more ions bond together. = different properties than the elements which formed it. = examples include water (H20) carbon dioxide (CO2) and halite or table salt (NaCl). Molecule = the smallest piece of a substance that retains the properties of that compound. Ex. NaCl = recipe for 1 molecule of salt Bonding = a group of processes that hold molecules together. = molecule “glue” Wicander and Monroe, @009, Essentials of Geology A Water Molecule is held together by covalent bonds = atoms in the molecule share electrons. 2H +1 + O-2 => H20 Garrison, 2012, Essentials of Oceanography Recipe for 1 molecule of water Water molecules are electrically neutral, but polarized. Their angular shape clusters the – charges on one side, and the + charges on the other side. Opposites still attract, so… http://www.free-extras.com/images/mickey_mouse-1101.htm A water molecule looks like Mickey Mouse, so they are electrically polarized. Fig.5.3, p. 131 Hydrogen bonds => The + end of one water molecule sticks to the – end of the next water molecule. http://www.qualityuswater.com/weregreen.htm Water has some special properties due to its polarized nature: Cohesion = water sticks to itself (hydrogen bonding) Surface tension = water has a thin “skin” on the surface can support light objects but they are NOT floating http://www.britannica.com/EBchecked/topic-art/575080/117360/Aluminum-coin-supported-by-the-surface-tension-of-water What causes surface tension? The molecules of a liquid are always trying to pull one another together. In the middle of a liquid, a molecule is pulled equally hard from all directions, so the attractive forces cancel out. But a molecule on the surfa ...

1. Element= a substance composed of many “identical” particles
called atoms.
= the most basic substances that matter can be broken into by
chemical means
= the “ingredients” making up everything
Chapter 5 – Water and Seawater
What elements are in water?
hydrogen (H) and oxygen (O)
Information about all known elements is shown in the Periodic
Table
Electron (-)
Proton (+)
Neutron
Nucleus
Electron Shells
The Parts
of an Atom
Atom = the smallest piece of an element that retains the
properties of that element.
Atoms contain two main parts and three types of subatomic
particles
Nucleus
Protons
Neutrons
Electron Shells
Electrons

2. Figure 5.1, p. 130
Particle NameWhere FoundElectrical ChargeMass
Y/N?OtherProtonNucleus+YesDetermines Type of
elementNeutronNucleusøYes# can change for the same
elementElectronElectron Shell-No# can change for the same
element
For an atom to be electrically neutral, # electrons = # protons
http://www.vtaide.com/png/atom.htm
Ion = an electrically charged atom.
# of electrons (-) ≠ the # of protons (+)
Negative ions (too many electrons)
Positive ions (too few electrons)
These will be attracted to each other.
Oxygen
O-2
Lithium
Li+1
http://itc.gsw.edu/faculty/speavy/spclass/chemistry/ions.htm
Compound = substance formed when two or more ions bond
together.
= different properties than the elements which formed it.
= examples include water (H20) carbon dioxide (CO2) and
halite or table salt (NaCl).
Molecule = the smallest piece of a substance that retains the
properties of that compound.
Ex. NaCl = recipe for 1 molecule of salt

3. Bonding = a group of processes that hold molecules together. =
molecule “glue”
Wicander and Monroe, @009, Essentials of Geology
A Water Molecule is held together by covalent bonds =
atoms in the molecule share electrons.
2H +1 + O-2 => H20
Garrison, 2012, Essentials of Oceanography
Recipe for 1 molecule of water
Water molecules are electrically neutral, but polarized.
Their angular shape clusters the – charges on one side, and the
+ charges on the other side.
Opposites still attract, so…
http://www.free-extras.com/images/mickey_mouse-1101.htm
A water molecule looks like Mickey Mouse, so they are
electrically polarized.
Fig.5.3, p. 131
Hydrogen bonds => The + end of one water molecule sticks to
the – end of the next water molecule.
http://www.qualityuswater.com/weregreen.htm
Water has some special properties due to its polarized nature:
Cohesion = water sticks to itself (hydrogen bonding)
Surface tension = water has a thin “skin” on the surface
can support light objects but they are NOT floating

4. http://www.britannica.com/EBchecked/topic-
art/575080/117360/Aluminum-coin-supported-by-the-surface-
tension-of-water
What causes surface tension?
The molecules of a liquid are always trying to pull one another
together. In the middle of a liquid, a molecule is pulled equally
hard from all directions, so the attractive forces cancel out. But
a molecule on the surface is only pulled downward. This
downward tug draws the surface of the liquid tightly together,
so it appears to have a skin.
http://www.daviddarling.info/childrens_encyclopedia/matter_Ch
apter3.html
Water has some special properties due to its polarized nature:
Cohesion
Surface tension
Adhesion -> why stuff gets wet
Dissolving ability = The polarized water
molecules can attach to and pull apart the
ions in compounds.
water is the universal solvent.
http://tasblogs.tas.edu.tw/wpmu/oliverf18109631/2010/11/24/33
/
http://bioap.wikispaces.com/Ch+3+Collaboration
See also figure 5.4, p. 131

5. Water Molecules dissolve salt crystals by pulling the sodium
and chloride ions apart.
Salt water is not water and salt,
it is water with chloride and sodium ions floating around in it.
Heat = The energy produced by the random vibration of atoms
or molecules -> depends on the rate of vibration and the number
of particles (mass).
Heat is stored energy
Heat is measured in calories
http://hop.concord.org/h1/phys/h1p.html
Temperature => measures only the rate of vibration and not
how many particles are vibrating.
Higher the temperature => faster vibration.
measured in degrees.
In the U.S. we use Fahrenheit degrees (°F)
In the metric system, we use Celsius degrees (°C)ScaleFreezing
pointBoiling pointconversionFahrenheit32 °F212 °FF-32° X
5/9Celsius0 °C100 °CC X 9/5 + 32°
Density = mass per volume = mass/volume. Density is a
measure of how “heavy” something is.
Density is measured in grams per cubic centimeter = g/cm3
Which is more dense? Why?
http://www.dimensionsguide.com/brick-sizes/
http://southernartistictouch.blogspot.com/2010/03/italian-bread-
bread-machine.html

6. The three states of matter:
Solid – atoms or molecules are “frozen” into a rigid structure
where they vibrate. Solids maintain their shape and size. Water
molecules experience hydrogen bonding.
Liquid – atoms or molecules have more energy and are moving
randomly. Liquids maintain their size but will change flow to
fill the bottom of their container. Water molecules still
experience hydrogen bonds, but they break and reform.
Gases – atoms or molecules have so much energy they move
rapidly past each other. Gases expand to fill their container.
Water molecules no longer experience hydrogen bonding.
Specific Heat Capacity = the amount of heat required to raise
the temperature of 1 gram of a substance by 1 °C.
Measured in cal/gm/°C or calories per gram per degree Celsius
Latent Heat = the amount of heat required to change an object’s
phase (added to melt, removed to freeze) . Note that there is no
change in temperature as the phase changes.
Measured in cal/gm or calories per gram.
Salt = inorganic solids dissolved in water –
these are not just table salt…
Salinity = the % of water, by weight, that is dissolved inorganic
solids (salts)
=> salinity is measured in parts per thousand ‰
1 ‰ = 0.1%
=> average ocean salinity is 35 ‰ = 3.5%

7. This means that if I evaporated 1000 cups of seawater I would
get 35 cups of salt!
http://article.wn.com/view/2010/11/22/Drilling_the_Dead_Sea_f
or_history/
Some definitions you should know:
Solution
= a homogeneous substance made of two components: a solvent
and a solute.
An example is saltwater.
Solvent = the dissolver.
Water is a great solvent.
Solute = what dissolves.
Salt is a solute.
Saturated