Colligative Lab (short)

First, print out this lab sheet to complete as you go along with this lab.

Purpose

• The purpose of this lab is to examine how adding sodium chloride to water affects the boiling point of the solution.

Hypothesis (answer on your lab sheet)

• Pure water normally boils at 100^oC. This changes when you add a solute (like sodium chloride) to the water creating a solution. What do you think will happen to the boiling point as the molality increases?

Procedure (READ THE PROCEDURE AS GIVEN ON YOUR LAB SHEET)

Calculations

1. Show all your work for the calculation of the molality of the solution with the 1.5 g of NaCl in the calculation section of the lab sheet! Make a list and identify the parts of the solution.

2. Next, calculate the molality for the other five solutions that were made (the various amounts of sodium chloride that was added). You do not need to show your work for these.

3. Put the molality you calculated for each into the data table found on the second page of the lab sheet.

Data

If you were absent for this lab, click here to get your data.

Graph (use this link for a graphing program similar to LoggerPro to graph the data)

• Graph:

  • x axis - Concentration (m)

  • y axis - Boiling Point (^oC)

• It's a linear graph so select curve fit, then select linear.

• Don't forget to label your axes, title the graph, give the graph type and equation.

Questions (make sure you answer the three questions on the lab sheet)