Reaction of Magnesium with Hydrochloric Acid
Purpose
To develop a method for measuring the volume of gas generated in a reaction
between Mg and HCl.
To develop a relationship between the mass of magnesium reacted and the volume
of hydrogen generated.
To acquire an understanding of limiting reactants.
Materials
plastic bin | rubber hose | glass bend | 1.0 M HCl |
100 mL graduated cylinder | test tube (25 x 200 mm) | 5.00 mL pipet | 0.5 g Mg ribbon |
ringstand and clamp | 1-hole rubber stopper | pipet filler | tap water |
Safety
Avoid skin contact with hydrochloric acid. Wear goggles at all times. Rinse skin
thoroughly if contact is made. Hydrogen gas is flammable.
Groups
You will work in groups of 3-4, assigned at
random or by the professor. One member of the group will be assigned as a
project manager; one as a computer operator; one or two as a laboratory
technician. See the group work page for
more information.
Procedure
Design an apparatus that will enable you to collect and measure the
volume of hydrogen gas generated using only materials found in the list above.
To facilitate speedy collection of data, your group may choose to set up two
separate sets of equipment. Check
your system(s) for leaks or cracks. React eight different masses of magnesium in
the range of 0.01 g to 0.10 g with exactly 5.00 mL of 1.0 M HCl in eight
separate trials. To the extent possible, try to spread the masses of magnesium
evenly over the entire range 0.01 g to 0.1 g. Use
an analytical balance to record the masses. For each trial, collect the
hydrogen gas until there is no more than one bubble produced per minute,
then record the mass of Mg you used and the volume of hydrogen generated, and make a note if any magnesium metal remains.
Repeat any suspicious trials
Questions
Laboratory Report
(Review the
Guidelines for Writing Laboratory
Reports)
The laboratory report
for this experiment will be a group report. All members of the group
should contribute in some way to the writing of the report. You will need
to include a title, a detailed procedure, results, discussion and conclusion,
and references. After the references, also include the answers to
questions 4 and 6 above. The answers to the other questions should be
incorporated into your results or discussion, as appropriate.
As this is a group report, please include a table at the end showing the percent contribution of each group member on the entire lab, including the report.
Follow your instructor's directions for submitting the lab report. You may be allowed to submit this report by paper, by the D2L dropbox, or by email (using a filename convention of Lastname1 Lastname2 Etc Limiting and a subject line in your email of "Chem 1061: Limiting Reactant Lab").