Intermolecular Forces

Pre-Lab Exercise                                             Intermolecular Forces

                                              F^-  Cl^-   Br^-  I^-  Unk                                           

                                         Halides in 80% acetone                                    

1.                  Determine the R_f value for the Cl^- ion in 80% acetone.

2.         Which halide ions are present in the unknown?

3.                  Determine the molar mass for each of the alkanes (pentane, hexane, heptane, octane).

4.                  List the intermolecular forces present in ethanol, acetone and ethyl acetate.

5.                  A student studies the effect of intermolecular forces on vapor pressure by immersing a filter paper covered temperature probe in a test tube containing hexane.  The initial temperature is 24.0°C and the temperature after 45 seconds is 8.4°C.  Calculate the rate of evaporation.