Sea Water Density “Mass per unit volume”

TEMPERATURE Water molecules are at the maximum distance from adjacent molecules due to hydrogen bonding== Minimum density.

Water makes Hydrogen Bonds Ice (solid phase) is a crystal with maximal number of hydrogen bonds per molecule (4) crystalline lattice configuration

Deep circulation in the Atlantic

1. The effect of salinity on density: Use hydrometer and thermometer to measure the density and temperature for three solution of different salinities: 10, 20, 35 ‰ Hydrometer must be floating Determine what the theoretical density should be at a given temperature and salinity.

The effects of Temperature on Density 2: The effects of Temperature on Density Use 35%o water. Warm this water to 30°C. Then chill it, measuring the density along the way with 2 minute intervals. Remove the hydrometer between measurements. Remove the hydrometer between measurements. 30 ºC 5 ºC

3. The Effect of Ice Formation on Density 1.Let ~1/3 of your sample to turn into ice. 2. Transfer the remaining liquid that does not freeze “brine” into graduate. (you need ~85 mL to float the hydrometer) 3. Measure the temperature with the thermometer and measure the density with a hydrometer at 5 o C. DO NOT STIR WITH THE THERMOMETER DO NOT LEAVE THE THERMOMETER IN THE FLASK WHILE FREEZING

4: Temperature vs Salinity Although not in the text, we will be setting up the internal wave tanks again: 1) Place the divider in the center and put 2.5 liters of cold (blue) fresh water in one half and 2.5 liters room temperature (red) fresh water in the other half. 2) Predict the outcome and then pull the divider. 3) After the tank settles, reinsert the divider ~1/3 of the tank and stir the layers together. 4) Pull the divider again and answer the questions.

1500 ml tap water 15 drops of yellow 1500 ml cold water 15 drops of blue