Properties of Water Chapter 2 Pages Marine Science Ms. Flick

Vocab 1.Basins 2.Renewable resource 3.Nonrenewable resource 4.Overfishing 5.Sublimation 6.Freezing points 7.Melting point 8.Boiling point 9.Variables 10.Independent variable 11.Dependent variable 12.Solvent 13.Solute 14.Solution 15.Solubility 16.Atom 17.Neutrons 18.Protons 19.Hydrogen bonding 20.Cohesion

Vocab Continued. 21.Hydrogen bonding 22.Cohesion 23.Surface tension 24.Salinity 25.Vaporization 26.Freezing 27.Condensation 28.Brackish 29.Estuaries 30.Neutral buoyancy

Our Oceans The ocean covers approximately 71% of Earth’s surface Our planet’s ocean can be divided into four oceans: – The Pacific – The Atlantic – The Indian – The Arctic Basins-large water covered areas between continents; commonly referred to as oceans Earth’s ocean contains 97% of the water on Earth That leaves only 3% of the planet’s water as fresh as opposed to salt 2/3 of that freshwater is contained in ice in glaciers and sea ice caps in Earth’s polar regions

Ocean’s Renewability The ocean is important for all living things and influences many of Earth’s processes The ocean is a resource that replenishes itself naturally over relatively short periods of time – Renewable resource Some resources, such as natural gas and minerals, are exhausted faster than they are naturally replaced – Nonrenewable resources Just because the ocean is considered a renewable resource doesn’t mean everything in it is – Overfishing-humans extract fish at rates faster than they can reproduce making the food source no longer renewable

Activity 1 Procedure 1.Prepare two beakers-1 w/ cold water, 1 w/ warm water 2.Measure and record the temperature of each 3.Place 15 drops of blue food coloring into the cold water and stir 4.What will happen if cold water (blue) from a pipette is added to the warm water carefully down the side of the beaker? Write down your hypothesis-if/then statement 5.Add droppers full of the cold blue water down the inside wall of the warm water beaker 6.Drop some on one side-then the opposite side 7.Note: the dropper tip should be placed immediately under the surface of the water 8.Write down your observations.

Activity 2 1.Prepare 2 beakers-1 w/ warm water and 1 w/ ice cubes 2.Measure the temperature of each beaker’s contents and record 3.Place several ice cubes in the water

Discussion 1.How can you explain our observations of Activity 1? 2.What are the ice cubes made of? 3.In Activity 1 the cold water stayed on the bottom. If the ice is colder than the water would you expect it to float on the water? 4.What issues would their be in nature if ice did not float on water?

Investigation 1: Freezing, Melting, and Boiling Follow the directions in your textbook on pages to complete this investigation. Write down your findings on your own sheet of paper.

Investigation 2: Surface Tension Follow the directions in your textbook on pages to complete this investigation. Write down your findings on your own sheet of paper.

Investigation 3: Floating and Sinking Follow the directions in your textbook on pages to complete this investigation. Write down your findings on your own sheet of paper.

Investigation 4: Solutions Follow the directions in your textbook on pages to complete this investigation. Write down your findings on your own sheet of paper.

Atoms Atom-the most basic particle of a unique element that has the properties of that element Neutrons-no electrical charge Protons-a +1 or a positive 1 charge Around the dense nucleus of each unique atom is a cloud of tiny, negatively charged electrons Look at figure 2.16-hydrogen atom Look at figure 2.17-oxygen atom Hydrogen and oxygen combine to make a water molecule

Water Molecules Look at figure 2.19-water molecules Hydrogen bonding-the attraction between water molecules Cohesion-the property of water making it attracted to other molecules of water via hydrogen bonding It is cohesion that allows water to form drops Surface tension-the attraction between molecules at a liquid’s surface

Salinity Salinity-the measure of dissolved salts in water Distilled water has no salinity Water is considered fresh if it contains 1 part per thousand or less of salts The average salinity of the ocean is 35 parts per thousand (35% salt)

Ocean Water Ocean water carries a lot of minerals The minerals come from: – Land: freshwater in streams and rivers contains salts and flows into the ocean – Inside the Earth: volcanoes, vents, and other processes at the seafloor spew minerals from below Earth’s crust – Atmosphere: carried by wind and deposited into the ocean

Phase Changes Vaporization- liquid to gas Freezing- liquid to solid Condensation- gas to liquid Pure water boils at 100 degrees C – 212 degrees F Pure water freezes at 0 degrees C – 32 degrees F Salt water boils and becomes a gas at a slightly higher temperature than freshwater Salt water freezes at a slightly lower temperature

Freshwater and Saltwater Meet Brackish-water that is somewhere between salt and fresh – Margrove forests and salt marshes Estuaries-where rivers meet the sea – Nurseries of the sea; provide home for many species of marine life Plants and animals living here can tolerate wide ranges in salinity b/c their always changing

Neutral Buoyancy Some organisms float on top of the ocean Others live near its bottom Others make their homes throughout the water column Organisms have features that assist them with floating and sinking or moving up and down- neutral buoyancy