HCl and Zn reaction lab
In this lab you will observe chemical reaction between zinc (Zn) atoms and hydrochloric acid (HCl), count zinc atoms, and
determine the amount (in grams) of hydrochloric acid is used in the reaction. Also, you will be describing this chemical reaction and
write balanced chemical equation.
Safety Precautions: Hydrochloric acid (6M) solution is toxic by ingestion or inhalation; severely corrosive to skin and eyes. Wear
splash goggles and wash hands with tap water before leaving the laboratory. Follow all laboratory safety guidelines.
Materials: test tube, test tube rack, 6 M HCl solution, zinc metal, match, small piece of paper, graduated cylinder.
Procedure: 1. Measure 5 mL of 6M HCl with graduated cylinder and pour it into the test tube.
2. Obtain a small piece of Zn metal, weigh it, and record its mass.
3. Put the Zn metal into the test tube with 6M HCl solution.
4. Cover the test tube with small piece of paper.
5. Observe the reaction, and touch the bottom of test tube to feel for any change in temperature.
6. After observing the reaction for about 3 minutes, remove the paper cover; then, light the match above the test tube as smoke comes
out.
7. Make observation as you light match.
8. Leave everything as it is (do not clean up) and go back to your seat.
Data Table
One mole average atomic mass of Zn (g) (look up periodic table)
Mass of Zn (g)
Molar mass (mole mass) of Zn (look up periodic table)
Molarity (M) of HCl
Volume of 6M HCl solution (mL)
Molar mass (one mole) of HCl (g) (look up periodic table)
1 mole = 6.022 x 1023 atoms
6 M (mol/L)
Observation and Questions:
1. Describe what happened as you dropped zinc metal into hydrochloric acid solution?
2. Describe what happened as you light the match? (step 6)
3. What three observations indicate a reaction is taking place?
4. What evidence indicates the reaction is finished?
5. Given the mass of zinc that was measured and recorded on the data table, how many mole(s) of zinc was placed in the test tube?
6. Given the mass of zinc that was measured and recorded on the data table, how many atoms of zinc were placed in the test tube?
7. How many chlorine atoms should have combined with the number of zinc atoms?
8. List the reactants of this reaction.
9. List eh products of this reaction.
10. Write a chemical equation using correct subscripts and solid (s), gas (g), and aqueous (aq) for the reaction between zinc and
hydrochloric acid.
11. Write a chemical equation using correct subscripts and gas (g), and for the reaction when you lighted match above test tube (step
6).
12. Was the reaction above a chemical or physical one? How can you tell?