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The Experiment:

Salt and Water Boiling

In this experiment students will add different amounts of salt to 150.0ml of water.   The mixture of salt and water will then be heated until it reaches a full boil.  At this point students will measure the boiling temperature of the solution and record it in the table below using a Vernier temperature probe to measure the temperature.  The mass of the salt to be added in each trial is listed on the left.  Before beginning the experiment students should calculate the salt concentration in the water, and the solution mass% of salt in each trial.

During the experiment students should take care to not let the water boil for too long.  Excessive boiling time will cause the solution to lose water, as the liquid water will be turned to water vapor.

PROCEDURE:

  1. Measure out 150.0ml of water in a graduated cylinder and add it to a small kitchen sauce pan
  2. Add the required mass of salt for the trial you choose.
  3. Turn the stove heat on to medium-high and place the salt and water mixture on the stove. 
  4. Immediately place the Vernier Temperature Probe into the solution to monitor the solution temperature.  Be careful to suspend the probe in the solution.  DO NOT let it rest on the bottom of the pan or the probe will measure the pans surface temperature rather than the temperature of the solution.
  5. When the solution comes to a full boil (large bubbles NOT little tiny ones), record the temperature on the chart below
  6. Repeat  steps 1-5 for the remaining trials, adjusting the salt mass as necessary for each trial
Trial Amount
of Salt (g)		 Salt Concentration (grams of salt /
ml of H2O)		 Solution Mass % of Salt (grams of salt / total grams in solution) Boiling Temperature
1 0g      
2 5g      
3 15g      
4 30g      
5 45g      
6 60g