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OCEANS AND SALINITY OBJECTIVES. I can explain that salt water has a 3.5% concentration of sodium chloride (salt ), or salinity. I can explain why saltwater is more dense than freshwater, causes the water on the bottom of the ocean to be saltier than water at the top of the ocean.
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OCEANS AND SALINITY OBJECTIVES I can explain that salt water has a 3.5% concentration of sodium chloride (salt), or salinity. I can explain why saltwater is more dense than freshwater, causes the water on the bottom of the ocean to be saltier than water at the top of the ocean.
Earth’s Oceans • 97%of Earth’s water • 5 oceans on Earth: • Pacific Ocean (biggest) • Atlantic Ocean • Indian Ocean • Arctic Ocean • Antarctic/Southern Ocean Continents and Oceans Video http://www.youtube.com/watch?v=oCW-dJyBrog
Ocean Fun Fact: • The Pacific Ocean is the largest and deepest ocean in the world---its deepest point is nearly 7 miles deep near the Philippines Islands. • United Streaming: Planet Earth Deep Oceans---clip on Ocean Creatures --http://player.discoveryeducation.com/index.cfm?guidAssetId=C78FEA40-C28E-45AA-902F-8EF3D6EB5BCD&blnFromSearch=1&productcode=US#
Ocean’s Salinity All the salt of the oceans—could form a 500 feet thick layer across the Earth, about the height of a 40-story office building. • Salinity: The amount of dissolved salts in a body of water • Oceans have about 3.5% salinity • Salt= Sodium Chloride= NaCl
Why so salty?? • Weathering break salt off of rocks (especially igneous rocks) on land • Everything eventually makes it way to the sea—so erosion carries the salt to the seas. • Salt is deposited into the oceans where it remains.
Why so salty?? • The salt in the ocean is not evaporated or frozen—left in the oceans! • Oceans that are located in very hot or very cold climates can have a higher salinity.
Why can’t we drink salt water? Your body’s cell • Drinking salt water causes your bodies cells to release water in an attempt to create balanced levels in your body. • This loss of water from cells destroys their functionality, leading to dehydration, seizures, unconsciousness and brain damage • Also, kidneys are overwhelmed with salt causing them to shut down which can kill you.
Making salt water drinkable:expensive and challenging, but doable • Florida, California, Texas and Virginia currently desalinate ocean water • The United States has the capacity to desalinate more than 1.4 billion gallons of water per day. • BUT this is LESS THAN 0.01 % of water use nationwide Planet 100- Water Desalination Explained
Check for Understanding: • Why is the ocean so salty? • Where does the salt come from? • Why can’t you drink ocean water? • What is the biggest ocean?
Density • The bowling ball and the foam ball below have the same amount of volume, or space. Which one has more mass?
Density Column • Hypothesis: Which materials do you think will rise to the top?
Density Notes • Density- A measure of how much matter is in a certain volume or space. • Density= Mass/Volume • Objects with ___lower__ density will float. • Objects with a __higher___ density will sink.
Density Column: Draw Conclusions • Order the following materials in order from the most dense to the least dense. • Explain how you know this.
Density & Salinity • How do you think that density has to do with the salinity of ocean water?
Salinity and Density Lab • Fill beaker #1 with 100 mL with blue freshwater • Fill beaker #2 with 100 mL of saltwater • Using the triple beam balance, find the mass for each and record it in the table. Make sure you reset your triple beam balance to 0 before taking measurements. • Calculate the density of the freshwater and saltwater using the formula Density=Mass/Volume • When finished, answer conclusion questions
Looking at the picture to the right, order the objects (Water, cube, crown) from most to least dense • Answer: • Crown (sank to bottom of water) • Water • Cube (floated on top of water)