This preview shows page 1. Sign up to view the full content.
Unformatted text preview: probe in the solution. Record the temperature when the solution first begins
to boil. Calculate the value of “i” for each substance.
Colligative properties: Dakota State University page 170 of 232 Experiment 16: Colligative Properties General Chemistry I and II Lab Manual The equation for boiling point elevation is ∆Tb=iK b m, where m is molality (moles of
solute per kilogram of solvent), and for water, the boiling point elevation constant, Kb, is
0.512 o C/m. Dakota State University page 171 of 232 Experiment 16: Colligative Properties General Chemistry I and II Lab Manual Observations: Diffusion:
Observations: Solubility of Ammonia:
Observations: Dakota State University page 172 of 232 Experiment 16: Colligative Properties General Chemistry I and II Lab Manual Solubility
Paraffin Oil Hexane Water Low Temperature High Temperature Observations: Temperature and solubility: Solute
Observations: Dakota State University page 173 of 232 Experiment 16: Colligative Properties General Chemistry I and II Lab Manual Colligative Properties:
ethylene glycol Dakota State University Boiling Point Value of “i” page 174 of 232 Experiment 16: Colligative Properties General Chemistry I and II Lab Manual Name:
Date: Solubility and Colligative Properties
1) List the salts we are using in part one and label them as polar or non-polar. 2)
What similarities do you notice in the salts used in the effect of temperature on
solubility? What differences? 3) What Colligative property are we studying? Dakota State University page 175 of 232 Experiment 16: Colligative Properties General Chemistry I and II Lab Manual Solubility and Colligative Properties
1) Do you expect that cooking oil is polar or non-polar? Explain your reasoning. 2) What did you notice about the freezing point depression? Can you explain it? 3) Look at the compounds we used for boiling point elevation and the value of “i” that
you calculated for each. What do you suppose “i” stands for? Dakota State University page 176 of 232 Experiment 17: Calorimetry General Chemistry I and II Lab Manual Experiment 17: calorimetry
Purposes: To measure heat transfer Ping: A noise made by expensive machines in operating rooms to impress the
See “Using the Pasco System” and “Basic Laboratory Procedures”; pipettes, balance
Ever wonder how it is that scientists come to draw the conclusions that have put
science where it is today? Today’s experiment is split into two parts; the first is designed
to get you to practice asking questions, blind, as it were, much as scientists were a
hundred years ago. Nowadays, it is easy to draw on the conclusions of scientists gone by,
Dalton’s atomic theory, the Bohr atom, as convenient starting points. But, what do you
do if you have no convenient starting point? Then the starting point becomes the most
basic; pure observation.
The next part of the experiment has several purposes; among them are t...
View Full Document