Physical Change Lab Report

PURPOSE

The purpose of this experiment is to investigate the process of reaching equilibrium in a physical change.

MATERIALS

2 Coffee stirrer sized straws*

Graduated cylinder, 100mL and 10mL

Plastic cups

*Couldn't get coffee stirrer sized, substituted with regular drinking straws.

PROCEDURE

Label a 25 mL graduated cylinder ”A”. Fill it to the 25.0 mL mark with water. This is the REACTANTS. Label a second 25 mL graduated cylinder ”B”. This is the PRODUCTS. This cylinder will begin empty. Why is it empty at this stage?

Obtain 2 straws of different diameter. Label these straws with “A” and “B”. Be sure to keep straw “A” with cylinder “A” and straw “B” with cylinder ”B”.

With a partner, simultaneously lower the straws into each of the graduated cylinders. When the straws reach the bottom of the cylinder each partner will place an index finger over the opening of the straw and then transfer the contents to the opposite graduated cylinder and allow the water to drain.

Accurately record the volume of water in each of the REACTANTS and PRODUCTS cylinders on the “transfer #1” space in the data table that follows.*Note that in the first transfer some reactants

Which shown by the graph, when the volume of both cups steady around 12.5 mL. From the experiment, the straws in this case represented the reaction rates from products to reactants and vice versa. The experiment demonstrated equilibrium once the reaction rate becomes equal. Some errors that occurred is water being lost during the transfers via straws. This can also be applied to measuring the graduated cylinder, which some water droplet remained on the containers. Some future experiment to conduct include: using different size straws to demonstrate equilibrium, or investigating what would happen in more reactants was added when the system is at