Zinc and Acid Lab Instructions
Safety Warnings
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Scenario: An engineering contractor wants to use pure zinc metal for part of a machine she is
designing. This machine has a chance of being exposed to strong acids. She wants to know if the zinc
will react with an acid, and if so, what material(s) will be produced?
Important notes: Zinc metal has 2 valence electrons. When drawing Lewis dot structures for transition
metals, the maximum number is 18 rather than 8. When nonmetals bond with nonmetals, they will
share electrons.
Pre-lab questions: (helpful things to include in the research section)
What do you know about zinc?
What do you know about hydrochloric acid? What type of bond is present?
How will you know if a chemical rxn (reaction) takes place?
Supplies:

Goggles

Test tube holder

HCl acid – 1 M

Large test tube

Pipette (w/ grad.

Zinc metal

Test tube rack
cylinder holder)

Page for notes
Instructions:
1. After you have completed the first 3 steps of the scientific method, find a pair of goggles that fit
snugly over your face. Wear them at all times until the instructor tells you otherwise.
2. Using the test tube holder, carefully lift a test tube and place it into a test tube rack and release.
3. Using the tongs, carefully select one piece of zinc metal (either the unprocessed zinc or processed
zinc squares) and place it in your test tube.
4. Carry the test tube holder and tray with test tube back to your seat and place it on the table.
5. Return to lab supply area and VERY CAREFULLY pick up a small graduated cylinder with pipette
inside. Pipette contains approximately 2 mL of 1 M hydrochloric acid. (Molarity is a measure of
concentration of solutions and mixtures). Return to seat carefully.
6. Make and record observations of zinc metal and HCl acid individually. Only hold the test tube with
test tube holder, never bare hands.
7. With test tube in the test tube rack, carefully lift the pipette containing the acid from the graduated
cylinder and place the tip approximately 2 cm above the sample of zinc in the test tube. Gently
squeeze until the majority of the HCl is in the test tube.
8. Place empty pipette back in graduated cylinder.
9. Using the test tube holder, lift the test tube up out of the rack. Be careful not to apply pressure to the
holder, accidentally releasing the test tube.
10. Kneel down so you are at eye level while your partner holds the tube. Make and record observations.
After your partner replaces the tube in the rack, trade places carefully. Continue to make detailed
observations and trade places for several minutes. NEVER look directly down into a test tube.
11. After several minutes, make final observations about any new materials formed (if any) and place the
test tube back in the rack. Take rack and test tube back to lab supply area. Transfer your test tube with
test tube holder to designated “Used Supply” rack. In a separate trip, return pipette (inside of
graduated cylinder) to lab supply area.
12. Wash your hands with soap and water and return to your seat.
Questions (include this information in your conclusion in paragraph form, along with normal conclusion
information):
1. Did a chemical reaction take place? How do you know?
2. Were there any new substances formed? What were they? Be sure and identify their chemical
formulas.
3. What types of bonds were present in the materials before and after the reaction? Show the Lewis dot
configurations for the beginning and ending substances.
4. What is the charge on the final compounds or molecules?
EC: Identify the balanced chemical equation for this reaction.
Important things to consider in your lab report
 There is more than one atom of each type in the test tube.
 All compounds or molecules at the end of the reaction are neutral/stable. Reactions occur so that atoms can become
stable.
 Keep in mind which atom has electrons to share and which wants electrons. How many?
 Typing = 5% EC (and its easier to do rewrites - unlimited)
 Use your Scientific Report Writing document to help write the lab report