Oct. 26 & 27 Welcome Assignment Extra Credit Word Search and Sudoku will not be accepted. The assignment is closed. Please take out your take home test and pass it forward. Take out a sheet of paper – Write name, period, and date – Title: Convection Currents/Density and our Ocean – Lab Activity

Convection Current/Density in our Ocean Lab Activity Research Question/Purpose: How do convection and density affect our ocean waters? How does the salinity of the water affect the current? Background information: –Convection = transfer of heat by a fluid (liquid or gas) –Density = the amount of matter in a given space. mass/volume

Materials 8 ice cubes (2 each trial) Fresh warm water Beaker tongs A ruler Thermometer 250ml beaker Salt (about 70 grams) Spoon Paper towels Timer

Procedure 1.Obtain an ice cube that has been strongly dyed with food coloring 2.Using the beaker tongs, gently place the ice cube in a beaker ¾ full of warm, fresh water. Keep the beaker and water as still as possible. 3.Observe the ice – water mixture for 5 minutes. Write a detailed description of your observations 4.Measure the temperature at the surface, at the bottom of the mixture, and 3 measured levels in between.

Procedures continued… 5.Empty the beaker and fill it to the same level with warm water. 6.Add salt to the water, stirring vigorously as you pour until no more salt will dissolve (saturated solution) 7.Repeat steps 3 and 4 using salt water in place of fresh water (do 2 trials of fresh water and 2 trails of salt water, first set for observations, second for temperature)

Trial 1 Fresh waterTrial 2 Fresh water Trial 3 Salty waterTrial 4 Salty water

Data/Observations Min Observations Fresh H2O Depth Temp of Fresh H20 Surface ½ Bottom Min Observations Salty H Depth Temp of Salty H20 Surface 1/2 Bottom

November 2 & 3 Homework Tonight TeenBiz3000 – 4 articles due Nov. 30 th –No Water –A new way to study the ocean –Walking on thin ice –What is happening under the earth Data analysis and Conclusion for Lab

Data Analysis Looking at the data, compare them. How does the Saltwater data differ from the Fresh water data? How are they the same? (you can draw a double bubble map)

Conclusion What errors may have hurt your results? How did the salt change the results? And Why? How might this saltwater model be an example of the ocean currents? How do convection and density affect our ocean waters? How does the salinity of the water affect the current?