Predicting Products Lab
Name__________________________________
Chemistry 5.0 - Equations
Period_______Date_______________________
Pre-lab Questions:
1. What constitutes a positive test for each of the following gases?
a. oxygen (O2):
______________________________
b. hydrogen (H2):
______________________________
c. water vapor (H2O):
______________________________
d. ammonia (NH3):
______________________________
e. carbon dioxide (CO2) ______________________________ and/or ____________________________
2. What is the proper way to smell a substance in the lab? __________________________________________
3. What is the role of a catalyst in a reaction? How can you tell if when a substance serves as a catalyst?
______________________________________________________________________________________
Materials:
goggles/apron
Bunsen burner
graduated cylinder
3 wooden splints
ammonium carbonate
cobalt chloride paper
0.1 M potassium iodide (KI)
copper carbonate (CuCO3)
manganese dioxide (MnO2)
2 pieces of magnesium ribbon
crucible tongs
watch glass
6 test tubes
test-tube rack
test-tube clamp
copper turnings
well plate
3% H2O2
spatula
limewater (Ca(OH)2 solution)
matches
0.1 M lead nitrate (Pb(NO3)2)
one-hole rubber stopper glass tube elbow
2.0 M Hydrochloric acid (HCl)
Procedure:
Read the procedure for each reaction in its entirety before doing it so that you have the necessary
materials to complete the procedure. Wear goggles and an apron throughout the entire lab. Be sure to
tie back long hair. Write detailed observations in the Chart on page 3. Follow disposal instructions.
Reaction 1:
Obtain a 3 cm piece of magnesium ribbon. Clamp the magnesium with a pair of crucible tongs.
Ignite the magnesium in a Bunsen burner flame and collect the ashes on a watch glass. Do not
look directly at the magnesium while it burns. Discard the product in the trash.
Reaction 2:
Obtain another 3 cm piece of magnesium. Add 5-10 mL of 3.0 M hydrochloric acid (HCl) to a
small test tube in a test tube rack. Add the magnesium to the acid. Using a test tube clamp,
invert a second test tube (as shown in the figure below) over the mouth of the reaction test tube
and collect the gas being produced. Keep the test tube inverted and test the collected gas by
inserting a flaming splint. See the picture on the next page. If all the Mg has reacted you may
dispose of the product in the sink.
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Reaction 3:
Reaction 4:
Obtain a piece of copper and weigh it. Using crucible tongs, hold the copper into a flame until it
turns red hot. Allow the copper to cool and weigh it again. Record the initial and final
appearances of the copper as well as the initial and final masses. Discard in the trash.
Reaction 5:
Obtain one scoop of ammonium carbonate, (NH4)2CO3, and place it into a small test tube.
Clamp the test tube and heat it in a Bunsen burner. While the test tube is heating, touch a piece
of cobalt chloride paper to the mouth of the test tube and remove it. Smell the test tube using the
proper wafting technique. Hold a flaming splint in the test tube and record the results of each
test. Discard the ammonium carbonate in the sink with water.
Reaction 6:
Measure 10 mL of hydrogen peroxide and add to a small test tube. Add a very small quantity
(tip of spatula) of manganese dioxide, MnO2, (catalyst) to the test tube. Place a glowing splint
inside the mouth of the test tube. Hold a piece of cobalt chloride paper to the mouth of the test
tube. Discard the solution in the trash.
Reaction 7:
Add 1 drop of potassium iodide, KI, and 1 drop of lead (II) nitrate, Pb(NO3)2, to a watch glass.
Record the results. Wipe off the watch glass with a paper towel and dispose in the trash. Be sure
to wash your hands well with soap and water.
Reaction 8:
Place two scoops of copper (II) carbonate, CuCO3, in a large test tube. Insert a stopper with a
glass bend in the test tube. Clamp the test tube to a ring stand on an angle so that the flame will
touch the bottom of the test tube only. Fill a small test tube approximately half way with
limewater. Position this test tube so that the end of the glass bend is in the test tube and is
submerged in the limewater. Light the Bunsen burner and heat the solid in the large test tube.
Observe any changes in the limewater and the solid. Dispose of the solid in the trash, the
limewater solution may be put down the sink. Clean up and wash your hands.
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Test Results
Reaction
#
Reaction
1
burning Mg
2
Zn and HCl
3
heating Cu
4
heating (NH4)2CO3
5
H2O2 and MnO2
6
KI and Pb(NO3)2
7
heating CuCO3
Observations
Cobalt
Chloride
Splint
Odor
Limewater
Questions:
1. Complete and Balance each equation using the test results above. Indicate the reaction type (synthesis, S,
decomposition, D, single replacement, SR, double replacement, DR, or combustion, C on the line provided.
Reaction 1:
type:__________________
___________________________________________________________________________
Reaction 2:
type:__________________
___________________________________________________________________________
Reaction 3:
type:__________________
___________________________________________________________________________
Why did the mass of copper change?__________________________________________________
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Reaction 4:
type:__________________
______________________________________________________________________________
Reaction 5:
type:__________________
______________________________________________________________________________
Reaction 6:
type:__________________
______________________________________________________________________________
Reaction 7:
type:__________________
______________________________________________________________________________
2. Write complete, balanced equations for each of the following:
a. When KBrO3 is heated, it decomposes into KBr and a gas that reignites a glowing splint.
b. Sodium metal reacts violently with water to produce NaOH and a gas that pops in the presence
of a flame.
c. When Ca(OH)2 is heated, it makes CaO and a substance that will turn cobalt chloride paper pink.
d. When CH4 is burned in the presence of O2 it produces a substance that will extinguish a flaming
splint and a substance that turns cobalt chloride paper pink.
3. Identify the reaction type for each reaction in question 2.
a._________________ b.________________ c._________________ d._______________
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