ocean 100 sacramentogrilo exam 2 Questions and
Answers
what makes up the water molecule? - -1. 2 hydrogen (+) atoms, attracts (-) atoms
2. 1 oxygen (-) atoms, attracts (+) atoms
-what is the bond angle of the water molecule? - -105°
-what's so peculiar about this molecule? - -it's one of the few molecules on earth present in
3 different ways: liquid, solid, & gas
-what kind of bonds are in the water molecule? - -covalent bonds (sharing electrons
between O & H atoms)
-what kind of bonds connect all the water molecules together to form liquid? - -hydrogen
bonds
-what do these bonds lead to? - -bind water molecules together; cohesion - > surface
tension
-why is water a polar molecule? - -b/c it has 1 side that is positively charged & 1 side that
is negatively charged
-what do we call water as a result & why? - -a universal solvent b/c it dissolves substances
-what happens to salt (NaCl) in water? - -it dissolves; na (+) atoms are attracted to o (-)
atoms & cl (-) are attracted to h (+) atoms
-what are the 3 phases of water? - -ice (solid), water (liquid), vapor (gas)
-how does 1 phase get changed to another? - -1. water - > ice (heat is removed)
2. ice - > water (heat is added)
3. water - > gas (heat is added)
-what is heat capacity? - -amount of heat required to raise the temperature of 1g of a
substance by 1°C
-what is the heat capacity of water? why? - -high heat capacity b/c water molecules don't
want to change (thermal inertia)
-what is the heat capacity of sand? why? - -low heat capacity b/c it takes little energy to
raise its temperature
, -how do the thermal properties of water influence coastal climates? - -oceans moderate
the coastal climate (winter & summer have similar temperatures & are moderate); inland
(winters & summers differ extremely b/c there is no ocean)
-how does salinity & temperature affect density? - -1. as salinity increases, density
increases
2. as temperature decreases, density increases
-what is density? - -mass per unit volume (g/cm3)
-what happens to cold, salty water? - -thermal contraction (molecules lose energy & slow
down & occupy less space)
-what happens to warm, brackish water? - -thermal expansion (molecules gain energy &
speed up & occupy more space)
-what does water do at the poles? why? - -contracts b/c it is cold, sinks b/c it is cold, salty,
& dense
-what does water do at the equator? why? - -expands b/c it is hot, rises b/c it is warm &
less dense
-what is the temperature of the maximum density of water? - -4°C (1g/cm3)
-how does the density of water change with freezing? - -density increases but later
becomes less dense after reaching a max temperature of 4°C
-why does ice float on water? - -b/c it is less dense (there is more space between its
molecules)
-what is salinity? - -total amount of dissolved solids (ions) in water
-what is the average salinity in the world's oceans? - -3.5% (35 parts per thousand)
-what are the most abundant salt ions? - -1. chloride
2. sodium
-what is the surface salinity like at the equator? - -salinity is in the middle (high
evaporation & high precipitation)
-what is the surface salinity like at subtropical latitudes (30°)? - -high salinity (high
evaporation, low precipitation, & low river runoff)
-what is the surface salinity like at high/polar latitudes? - -low salinity (high precipitation,
low evaporation, river runoff, & melting icebergs)
Answers
what makes up the water molecule? - -1. 2 hydrogen (+) atoms, attracts (-) atoms
2. 1 oxygen (-) atoms, attracts (+) atoms
-what is the bond angle of the water molecule? - -105°
-what's so peculiar about this molecule? - -it's one of the few molecules on earth present in
3 different ways: liquid, solid, & gas
-what kind of bonds are in the water molecule? - -covalent bonds (sharing electrons
between O & H atoms)
-what kind of bonds connect all the water molecules together to form liquid? - -hydrogen
bonds
-what do these bonds lead to? - -bind water molecules together; cohesion - > surface
tension
-why is water a polar molecule? - -b/c it has 1 side that is positively charged & 1 side that
is negatively charged
-what do we call water as a result & why? - -a universal solvent b/c it dissolves substances
-what happens to salt (NaCl) in water? - -it dissolves; na (+) atoms are attracted to o (-)
atoms & cl (-) are attracted to h (+) atoms
-what are the 3 phases of water? - -ice (solid), water (liquid), vapor (gas)
-how does 1 phase get changed to another? - -1. water - > ice (heat is removed)
2. ice - > water (heat is added)
3. water - > gas (heat is added)
-what is heat capacity? - -amount of heat required to raise the temperature of 1g of a
substance by 1°C
-what is the heat capacity of water? why? - -high heat capacity b/c water molecules don't
want to change (thermal inertia)
-what is the heat capacity of sand? why? - -low heat capacity b/c it takes little energy to
raise its temperature
, -how do the thermal properties of water influence coastal climates? - -oceans moderate
the coastal climate (winter & summer have similar temperatures & are moderate); inland
(winters & summers differ extremely b/c there is no ocean)
-how does salinity & temperature affect density? - -1. as salinity increases, density
increases
2. as temperature decreases, density increases
-what is density? - -mass per unit volume (g/cm3)
-what happens to cold, salty water? - -thermal contraction (molecules lose energy & slow
down & occupy less space)
-what happens to warm, brackish water? - -thermal expansion (molecules gain energy &
speed up & occupy more space)
-what does water do at the poles? why? - -contracts b/c it is cold, sinks b/c it is cold, salty,
& dense
-what does water do at the equator? why? - -expands b/c it is hot, rises b/c it is warm &
less dense
-what is the temperature of the maximum density of water? - -4°C (1g/cm3)
-how does the density of water change with freezing? - -density increases but later
becomes less dense after reaching a max temperature of 4°C
-why does ice float on water? - -b/c it is less dense (there is more space between its
molecules)
-what is salinity? - -total amount of dissolved solids (ions) in water
-what is the average salinity in the world's oceans? - -3.5% (35 parts per thousand)
-what are the most abundant salt ions? - -1. chloride
2. sodium
-what is the surface salinity like at the equator? - -salinity is in the middle (high
evaporation & high precipitation)
-what is the surface salinity like at subtropical latitudes (30°)? - -high salinity (high
evaporation, low precipitation, & low river runoff)
-what is the surface salinity like at high/polar latitudes? - -low salinity (high precipitation,
low evaporation, river runoff, & melting icebergs)
