Inversion Of Sucrose (IS)
Objective
The purpose of this experiment is to determine the rate constants for the acid catalyzed hydrolysis of sucrose at three temperatures and then determine the energy of activation.

Special Instructions
You will use the Kern polarimeter in which angle of rotation readings are taken manually.

Introduction To The Inversion Of Sucrose
The polarimeter has an initial filter that acts to orient electromagnetic radiation in a certain
plane (plane polarized light). A crude analog is trying to swing in a circle a rope that extents through a picket fence. The rope would only be able to move up and down in the same directions as the opening between pieces of fence. This plane polarized light can be rotated to a positive or negative angle by an optically active compound containing a chiral carbon. The polarimeter has a second filter that can be rotated to determine the angle of rotation.

The pure forms of R and S enantiomers would each rotate the polarized light in opposite
directions. An optically active compound that causes a positive (+) or clockwise rotation is
referred to as dextrorotatory. An optically active compound that causes a negative (–) or counterclockwise rotation is referred to as levorotatory. Recall that R and S indicate the
arrangement of groups about a chiral carbon but will not tell you which direction plane polarized light is rotated. An R compound could give either + or – rotation and the corresponding S compound would then be the opposite. In this experiment the rate of the acid catalyzed hydrolysis of sucrose will be studied as a function of temperature.

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