Chemical Change Lab

Cornerstone Chemistry
Investigating the Fundamentals of
Chemical Change

For Student-Scientists enrolled in

Introductory Chemistry Laboratory 106
11th Edition

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Table of Contents
Introduction
A Few Words

3

Acknowledgments

3

Becoming a Novice Scientist

4

The Laboratory Notebook

5

Responsibilities and Grading

9

Safety and Disposal

12

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Experimental Activities
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Lab 1 : South Street Seaweed Seaport

15

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Lab 2: A Library for Chemists

30

Lab 3: The Redox Arena

45

Lab 4: The Castle of Quantification

59

Lab 5: Take the A Train

69

Lab 6: Grand Central Equation

76

Lab 7: 6B1h and Zinc

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Lab B: Liberating Gas

102

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Lab 9:…show more content…
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Quantitative Measurements of the Solute
Since the solute is the species involved in chemical transformations, our goal will be the determination ot"the number of moles of solute in a particular solution. To be definitive, you want to carry out a reaction that involves zinc iodide. Instead of getting the zinc iodide in the solid state, you go in the .lab and there is a flask that contains zinc iodide diss91ved in water (in the solution state). What might the label on the flask say that will tell you how much iodide there is in the water?
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There are numerous measures of the amount of solute in solvent. Try this exercise.

Exercise 1. Devise a measure of solute concentration that you would place on the label for the following case: You weigh out 2.56 g of zinc iodide: You put the solid zinc iodide in a 500 mL flask and fill the flask with water to ttie 500-ml nia'rk. You now have sao mL of a zinc iodide aqueous solution. On the label of the flask you write (there ca'n be many different possibilities):

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Exercise 2. Two students need zinc iodide that is in solution in the following amounts:
Student 1 : 0.43 g of zinc…show more content…
Do this before it cools or water will travel backwards into your tube and contaminate your solid product.

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Collecting a liquid product: If you loosely wrap a damp paper towel around the upper-outer section of the boiling tube away from the flame, you might be able to condense a gaseous produCt into its liquid ·state. In addition to this you should cut a large piece of qualitative filter paper in half and then fold it and theri curl it inside the boiling tube near the rubber stopper. If a liquid forms, the finer paper will help absorb it and prevent it from falling back onto the solid being heated. Make sure the rubber stopper is securely in place since gas can easily leak out.
Collecting the gaseous product: Prepare the gas collection bottle by positioning the bottle so that its mouth is. directly over the hole at the bottom of the trough; this is where the gas will enter the bottle. After the reaction, slide a square of glass over the mouth of the bottle while the bottle is still under water. Keeping the glass fixed to the mouth, raise the collection bottle and invert. Keep the square on the bottle or the gas will escape.
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Detach the rubber stopper from the boiling