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Rate of Solvation
Task with Student Directions
Contributed by: Council of Chief State School Officers (CCSSO)


Welcome to this experimental science test. We hope that you will find it interesting and worthwhile. Carefully read through these directions and the directions on the next page before you begin to work.

You may be part of a group for the first part of this exercise. Each group should carry out the experiment and collect the data together, but each student must record the data in his or her own booklet. Be sure to record the data exactly as you observe them. After the data have been collected, each student should answer the questions independently.

After you have finished your experiment and have recorded all of the data, you will be asked to answer some questions about the experiment and the data you recorded. Your answers must be written in this test booklet in the space provided. Make sure that you understand each question before you begin to write. At any time while you are writing your answers, you may look back at the directions for the experiment and the data you collected. Be sure that your answers are written as clearly and neatly as possible.

Before you turn the page, read the list of materials given below and check to make sure that your group has everything listed.

Materials in the Kit
  • sugar cubes
  • stirrers
  • thermometer
  • 5 cups
  • 5 250 mL measuring cup
Materials Supplied by the School
  • Bunsen burners, alcohol burners, or hot plates
  • paper towels
  • safety goggles
  • Pyrex beakers
  • ice
  • beaker tongs or hot pads
  • tap water
  • pen or pencil



Factors Affecting the Rate of Solvation

Solvation refers to the process of dissolving a solute (e.g., sugar) in a solvent (e.g., water). Many factors influence the rate at which a solute dissolves. The purpose of this exercise is for you to determine what sorts of factors affect the time it takes for a sugar cube to dissolve in water.

Read all of the instructions before beginning the exercise. You will be working in groups while performing the experiments and collecting data. Each member of the group must record the data in his or her own booklet. You will be working alone while responding to the questions.

Label your first data "Data Set 1" and record it under Question 1 on page 5. Now pour 75 mL of water into one of the cups. Measure the initial temperature of the water and record it in "Data Set 1." Add one of the sugar cubes and begin stirring. Record the time it takes for the sugar cube to dissolve in "Data Set 1."

Using the provided materials and equipment, you will now design and perform two studies. One of the studies should test the effect of temperature on the time it takes for a sugar cube to dissolve in water. The other study should test the effect of another factor that you think would affect this time. Collect as much data as you feel are necessary. Be sure to record all relevant data under Question 1 for later analysis. Be sure that each of these two data sets is labeled to indicate the factor that is being studied.

After you have complete this part of the exercise, be sure to clean up your work area.


Please answer the following questions by yourself.

1. Record your data and observations from your studies in the space provided. Include a description of the procedures you used in each of your studies.





2. Using what you know about science, explain why the factor you tested in each study affected the time it took for the sugar cubes to dissolve.







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