Recrystallization Experiment Lab Report by Kayla Wirth [Student FVHS]

Pre-Lab Discussion:

17wirthkm037 — 2013-11-14 19:56:32 UTC

Recrystallization is one way of isolating an ionic compound from a solution.

If several ionic compounds are present in an aqueous solution, then a precipitation reaction may be performed to remove the unwanted ions.

In this experiment, a known amount of NaCl will be dissolved in some water, and then recrystallized by boiling off the water.

Purpose of Experiment

17tobw238 — 2013-11-14 19:58:43 UTC

Learn to....

To perform and master a recrystallization of an ionic compound
To write a procedure for a simple experiment
To calculate for percent error in an experiment
To understand how results affect percent error

To identify sources of error in experiments

Heating Plate

17wirthkm037 — 2013-11-14 19:58:48 UTC

Tongs

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Graduated Cylinder

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Beaker

17wirthkm037 — 2013-11-14 20:00:57 UTC

Watch Glass

17wirthkm037 — 2013-11-14 20:01:07 UTC

Materials

17tobw238 — 2013-11-14 20:01:11 UTC

Flask

17wirthkm037 — 2013-11-14 20:02:18 UTC

Procedure

17tobw238 — 2013-11-14 20:03:34 UTC

Your group will need to write their own procedure for the experiment.
Use the lecture on error analysis as a guide.
Include a flow chart that mirrors each step in your procedure
Remember to include all the equipment that you use in your materials list

Electronic Balance

17wirthkm037 — 2013-11-14 20:04:44 UTC

Percent Error for our Experiment

17wirthkm037 — 2013-11-14 20:07:16 UTC

During the experiment, we had a 0% error on all three trials.

If our percent error was positive, what might have caused it?

17wirthkm037 — 2013-11-14 20:08:04 UTC

If the percent error was positive, then it means that extra

salt was obtained somehow, water was left in the beaker,

or the materials we used were dirty and had objects left

inside of them.

If our percent error was negative, what might have caused it?

17wirthkm037 — 2013-11-14 20:08:33 UTC

If the percent error was negative, that means we lost some salt along the way. The salt could have bounced out while the water was boiling, or we spilled some salt when pouring it out causing us to be inaccurate.

Which ESLR or ESLR’s were addressed in the activity?

17wirthkm037 — 2013-11-18 20:00:40 UTC

The ESLR that was addressed in the activity was "Critical Thinker". We decided it was this because we had to think about how we were able to get a 0% error on all three trials. We figured it we were accurate and precise and that we did everything correctly throughout the experiement.

4) Letting it Cool

17wirthkm037 — 2013-11-19 19:41:14 UTC

When all of the water had boiled off, we took it off of the heating plate and let it cool on the counter tops.

2) Weighing the Salt Water Solution

17wirthkm037 — 2013-11-19 19:44:15 UTC

Then, we zeroed the flask and measured the weight of the solution in grams

5) Weighing it Again

17wirthkm037 — 2013-11-19 19:44:28 UTC

Finally, when it had cooled slightly, we weighed it again on the electronic balance

3) Boiling the Solution

17wirthkm037 — 2013-11-19 19:44:49 UTC

After we weighed it and recorded the data and waited for the all the water to boil off

1) Mixing the Salt and Water

17wirthkm037 — 2013-11-19 19:45:05 UTC

First, we mixed the salt and water solution in a flask

Procedure

17wirthkm037 — 2013-11-19 19:47:40 UTC

Trial #1

17wirthkm037 — 2013-11-20 03:35:53 UTC

Trial #2

17wirthkm037 — 2013-11-20 03:36:59 UTC

Trial #3

17wirthkm037 — 2013-11-20 03:38:45 UTC

17wirthkm037 — 2013-11-20 03:41:19 UTC

(Tables made by Aniqa)