Period 2

Group 8

NaCl. Use a mass of about 1-2 grams.

Several pieces of glassware

Heating plate

Electronic balance

Beaker

Flask

Watch Glass

Rubber Tongs

Graduated Cylinder

2) and put 1 to 2 grams of salt

3) put water into graduated cylinder for 25 mL

4) add water to flask with salt

5) mixed water with salt so they dissolve

6) weighed the beaker

7) add dissolved water to beaker

8) put watch glass over and out it on the heater

9) after water exaporated let it cool down with out watch glass on top

10) weighed beaker with recrystalize salt

11) checked percent error

A) The percent error equations are on the data tables.

2) If your percent error was positive, what logical sources of error might have been the cause? Explain. Answer this question regardless of what your results were.

A) our 1st trial we got a 0% because we didnt lose any salt our have extra water in it. Trial 3 we got a 1% error because we had a little bit of extra water.

3) If your percent error was negative, what logical sources of error might have been the cause? Explain. Answer this question regardless of what your results were.

A) Trial 2 we got -8% error because we did not measure the watch glass and it had some salt on it

4) Which ESLR or ESLR’s were  addressed in the activity? State the ESLR and explain why in a short paragraph.

A) We used critical thinker because we had to process extra pictures and a video to process into the padlet wall with the modern technology.

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:  

You will 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