This document outlines a lab experiment to investigate the differences in freezing rates between salt water and fresh water. The goals are to observe and take temperature measurements as each type of water cools and freezes. Students will compare the freezing temperatures and hypothesize why salt water freezes at a lower temperature than fresh water. The lab will integrate concepts around states of matter, ocean salinity, saturation, and climatology. Equipment needed includes a temperature probe to collect data during the experiment.

1. CLASH OF THE SEA
Sea Water vs. Fresh Water
Which will feel the freeze
first?
Don Nenninger

2. CLASS UNIT GOAL:
THE INVESTIGATION AND STUDY OF
THE DIFFERENCE IN FREEZING TIMES
OF SEA AND FRESH WATER AS PART
OF A LARGER
UNIT IN METEOROLOGY.

3. GOALS OF THIS LAB
 1. Investigate the differences in the rate of freezing between salt
and fresh water and apply that to our unit in meteorology.

4.  Objectives
Lab Overview  In this experiment, you will
1. Safety  Observe the freezing of fresh
2. Procedures water and ocean water.
3. Observations  Use a Temperature Probe to
4. Data measure temperature.
5. Technology integration  Determine the freezing
6. Core Curriculum integration temperature of fresh and ocean
7. Literacy integration water.
8. Inquiry methods (Vernier)
9. Ecology impact

5. LAB SETUP AND PROGRESS
 Introduction
 During winter in the Northern Hemisphere, Arctic air temperatures
often dip below what we normally think of as the freezing point of
water. Yet, while freshwater lakes freeze over, much of the ocean
stays in liquid form rather than freezing into ice. Why doesn’t
ocean water freeze at the same temperature as fresh water?
 In this experiment, you will use a Temperature Probe to measure
the temperature of water as it cools and then freezes. In Part I,
you will collect temperature data as you freeze fresh water and
determine its freezing temperature. In Part II you do the same for
ocean water. You will then compare the two freezing temperatures
and hypothesize why they are different. (Vernier)

6. NY STATE CORE CURRICULUM
 C.1.M1.1.b.6Grades: 9-12
Science
 identify relationships within variables from data tables
 C.1.S3.1.aGrades: 9-12
Science
 organize observations in a data table, analyze the data for trends or patterns, and interpret the
trends or patterns, using scientific concepts
 C.7.2.1.bGrades: 9-12
Science
 gather and process information
 L.1.2.4Grades: 9-12
Science
 Carry out a research plan for testing explanations, including selecting and developing
techniques, acquiring and building apparatus, and recording observations as necessary.
 4.C.3.1.xxivGrades: 9-12
Science
 describe the processes and uses of filtration, distillation, and chromatography in the separation
of a mixture
 4.L.14Grades: 9-12
Science
 Organizes data through the use of data tables and graphs
 4.L.5Grades: 9-12
Science
 Makes observations of biological processes (Vernier)

7. LAB EQUIPMENT-SPREADSHEET-RESOURCES

8. LAB EQUIPMENT-SPREADSHEET & RESOURCES
Here’s a link to a similar lab sponsored by NASA
http://aquarius.nasa.gov/pdfs/prop_fresh_sea.pdf

9. SEA WATER VS. FRESH WATER
COMPARED
 Sea Water  Fresh Water
Average Temperature
Reading 1 _____ _____
Reading 2 _____ _____
Reading 3 _____ _____
Reading 4 _____ _____
Reading 5 _____ _____

10. Student Analysis
 https://www.google.com/search
?q=question+mark&ie=utf-
8&oe=utf-
8&aq=t&rls=org.mozilla:en-
1. Inquiry US:official&client=firefox-a#
2. Investigate
3. Research
4. Explore
5. Study

11. Unit Integration
1. Change of state
2. Salinity of the oceans
3. Saturation and super
saturation
4. Climatology
5. Effect on the planet

12. LINK TO YOUTUBE http://youtu.be/jatOw68Lr
Note: Unfortunately for MAC usersb4 PowerPoint you can’t
of
currently embed the code into the presentation and the raw
file is too large to include here.
The “Video from Web Site…” feature is not currently available in Office for Mac 2011. Mac
MVP Jim Gordon recommends the following solution:
“Copy the URL from the information to the right of the video. Paste that into a web site that
can download the file. I know of two sites that do this for free:
http://www.mediaconverter.org/
http://www.mediaconvert.com/
References:
Lab Experiment provided by Vernier Corporation:
http://www.vernier.com/experiments/esv/17/freezing_of_ocea
n_water/#standards (overall and slides, 5 and 6)