2 record the mass of the sodium chloride in the data

This preview shows page 108 - 111 out of 250 pages.

We have textbook solutions for you!
The document you are viewing contains questions related to this textbook.
Chemistry: Principles and Practice
The document you are viewing contains questions related to this textbook.
Chapter 3 / Exercise 09
Chemistry: Principles and Practice
Reger Chem
Expert Verified
2.Record the mass of the sodium chloride in the data table. If it is too small to read, click on theBalance area to zoom in, record the reading, and then return to the laboratory.3.100 mL of water is already in the calorimeter. Use the density of water at 25°C (0.998 g/mL) to determine the mass from the volume and record it in the data table. Make certain the stirrer is On(you should be able to see the shaft rotating). Click on the green heater light on the control panel to turn on the heater and begin heating the water. Click the clock on the wall labeled Accelerateto accelerate the laboratory time if necessary.4.Observe the temperature until the first appearance of steam comes from the calorimeter. Immediately click the red light on the heater to turn it off and then record the temperature as the boiling point of pure water in the data table. Letting the water boil will decrease the mass of the water present in the calorimeter. Note that the boiling point may be different than 100°C if the atmospheric pressure is not760 Torr. The current atmospheric pressure for the day can be checked by selecting Pressureon the LED meter on the wall.5.Drag the weigh paper to the calorimeter and add the NaCl. Wait 30 seconds for the salt to dissolve and then turn on the heater. When steam first appears observe and record the temperature in the data table.6.If you want to repeat the experiment, click on the red disposal bucket to clear the lab, click on the Stockroom, click on the clipboard, and select Preset Experiment #2, Boiling Point Elevation – NaCl.Data Tablemass NaClmass waterboiling temp of pure waterboiling temp of solution7.The boiling point elevation can be predicted using the equation T=Kb×m×i, where Tis the change in boiling point, iis the number of ions in the solution per mole of dissolved NaCl (i= 2), mis the molality of the solution, and Kbis the molal boiling point constant for water which is 0.51°C/m.Calculate the predicted change in boiling point, in EC for your solution.101
We have textbook solutions for you!
The document you are viewing contains questions related to this textbook.
Chemistry: Principles and Practice
The document you are viewing contains questions related to this textbook.
Chapter 3 / Exercise 09
Chemistry: Principles and Practice
Reger Chem
Expert Verified
Colligative Properties8.The change in boiling point must be added to the boiling point of pure water in your experiment inorder to compare the predicted boiling point with the actual boiling point.What is the calculated boiling point of the solution? Compare this with the actual boiling point.102
Freezing Point Depression4-5: Freezing Point DepressionIf you dissolve a substance such as ordinary table salt (NaCl) in water, the freezing point of the water will decrease relative to the freezing point of the pure water. This property is used to melt the snow or ice on roads during the winter or to make homemade ice cream. In this assignment, you will dissolve a sample of NaCl in water, add some ice, and then measure the freezing point depression.

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture