Types of Reactions
Purpose: The purpose of this lab is to observe some chemical reactions and identify the
reactants and products of the reactions. Also, to classify each reaction and to write
balanced equations.
Purpose:
Synthesis
Experiment 1:
1. Examine a piece of copper and note its appearance
2. Using tongs, hold the copper in the hottest part of a burner flame for 1-2 minutes
3. Examine the copper and note any changes
Experiment 2:
1. Place a watch glass near the base of the burner
2. Examine a piece of magnesium ribbon. Note its appearance
3. Using tongs, hold the magnesium in the flame until it starts to begin
CAUTION: do not look directly at the flame,
4. Hold the magnesium away from you and over the watch glass until it stops
burning. Put the remains in the evaporate dish. Make final observations.
Decomposition
Experiment 3:
1. Place a spatula full of potassium chlorate (KClO3) in a crucible. Make
observations
2. Heat to melting
3. Light a wood splint. Blow out the flame and insert the glowing end into the
crucible to test for oxygen gas. (CAUTION; do not allow your splint to fait into
the liquid)
Experiment 4:
1. Place two heaping spatulas full of copper (II) carbonate (CuCO3) into a clean, dry
test tube. Make observations.
2. Using a test tube holder, heat the CuCO3 strongly in a burner flame for about 3
minutes.
3. Light a wood splint and then extinguish the Bunsen burner
4. Insert the burning splint into the test tube to test for the presence of carbon
dioxide (CO2) gas- Note any change in the material in the test tube.
Single Replacement
Experiment 5:
1. Place a clean, dry test tube in a test tube rack
2. Add about 5 mL of 6m hydrochloric acid (HCl) to the test tube
(CAUTION: handle the acid with care. It can cause painful burns
3. Make observations of HCl and Zinc
4. Carefully drop a small piece of zinc into the test tube.
5. Using a test tube holder, carefully invert another test tube over the top of the first
one
6. Wait approximately 30 seconds to collect the gas
7. Remove the inverted tube and quickly insert a burning splint into the mouth of the
tube to test for hydrogen gas. Make final observations
Experiment 6:
1. Add about 5 mL of copper (II) sulfate (CuSO4) solution to a clean, dry test tube
2. Make initial observations of CuSO4 and Zinc
3. Place a small piece of zinc metal into the solution
4. Shake test tube occasionally
5. Wait at least 10-15 minutes. Make final observations
Double Replacement
Experiment 7:
1. Make initial observations of both chemicals
2. Add about 2 mL of potassium iodide (KI) to a clean, dry test tube
3. Add 2 drops of lead nitrate (Pb(NO2)3) to the same tube
4. Make final observations
**Caution – do not put this reaction down the drain
Experiment 8:
1. Make initial observations of both chemicals
2. In a clean test tube place 5 drops of iron (III) chloride (FeCl3) add 1 to 3 drops of
potassium thiocayanate (KSCN)
3. Make final observations
Observation Table:
Sample
Cu
Mg
KClO3
CuCO3
Before
During
After
Balanced Equation
Solid
Thin
Shiny
Bronze
Darker
color,
silver
edges
Gray solid
darker
2Cu(s)+ O2(g)2CuO(s)
Silver
Thin strip
shiny
Bendable
Bright
white
light
white
powder
solid
2Mg(s)+O2(g)2MgO(s)
white crystals
solid
Melting
Clear
liquid,
bubbling
Cracking
noise
Smoke
Positive test
for oxygen
2KClO3(s)3O2(g)+2KCl(s)
Green powder
Burning
Turns
black
Dancing
Positive test
for carbon
dioxide
Black solid
CuCo3(s) CO2(g)+ CuO(S)
Type
Synthesis
Synthesis
Decomposition
Decomposition
Zn &
HCl
Zinc- small
gray,
HCl- Clear
aqueous
solution
Bubbling
,bubbles
exploding
on top
Positive
Test for
hydrogen
Zn(s)+2HCl(aq)ZnCl2(aq)+H2(g)
Single
Replacement
Zn &
CuSO4
Zinc- small
gray
CuSO4- Blue
aqueous
solution
Solid
chunks,
zinc
breaking
up
Bronze
solid, blue
liquid,black
chunk
Zn(s)+ CuSO4(aq)ZnSO4(aq) +
Cu(s)
Single
Replacement
Pb(NO3)2
& KI
Lead nitrateclear liquid
solution
Liquid,
solid
particles
forming,
cloudy
liquid,
solid
chunks
Clear
liquid,
yellow solid
chunks
Pb(NO3)2+2KI2K(NO3)+Pb
l2
DoubleReplacement
Potassium
iodine- clear
liquid solution
FeCl3 &
KSCN
Iron Chlorideorange liquid
solution
Black
liquid, red
outer trim
Potassium
thiocyanateclear liquid
solution
Red stain on
test tube,
Black thin
liquid sticks
to side, no
chunks
FeCl3+3KSCN
3KCl+Fe(SCN)3
DoubleReplacement
Questions:
1. The test used to test for Carbon Dioxide gas was a wood splint test. A burning wood
splint was entered into the test tube. If the splint was extinguished there is Carbon
Dioxide present.
2. To test for hydrogen, a burning splint is placed in the test tube. If it makes a popping
noise, hydrogen gas is present.
Example: 2H2(g) + O2(g)  2H2O(l)
3a. AgNO3(aq)+Cu(s)  CuNO3 + Ag
Single Replacement
b. BaCl2(aq) + Na2SO4(aq)  NaCl + BaSO4
Double Replacement
c. Cl2(g) + 2NaBr(aq)  2ClBr + 2Na
Single Replacement
d. 2KClO3(s)  3O2 + 2KCl
Decomposition
e. AlCl3(aq) + 3NH4OH(aq)  3NH4Cl + Al(OH)3
Double Replacement
f. 2H2(g) + O2(g)  2H2O(l)
Synthesis
Conclusion:
The purpose of this lab is to observe some chemical reactions and identify the
reactants and products of the reactions. Also, to classify each reaction and to write
balanced equations.
A new lab technique used in this lab was the splint test which tested for Carbon
Dioxide gas. A lite wood splint is entered into a test tube with the solution. If the flame
was extinguished then the test is positive for the gas.
A new technique used in this lab was predicting products. Predicting products is
writing a balanced equation from the given solutions. Table F in the Chemistry Reference
Table is needed when finding the state of matter that solutions are. When doing single
replacement Table J is needed to see if some solutions can replace others.
Synthesis is a reaction that is a combination of two solutions to form a new
solution. A formula for synthesis is A + BAB. An example of synthesis is 2Cu(s)+
O2(g)2CuO(s). Copper and Oxygen combined to form a new solution.
Decomposition is a reaction where a single solution separates to form two
different solutions. A formula for decomposition is ABA+B. An example of
decomposition is 2KClO3(s)3O2(g)+2KCl(s) where potassium chlorate forms oxygen and
potassium chloride.
Single replacement is a reaction when a single element replaces another that was
in a compound. A formula for single replacement is AB + CAC + B. An example of
single replacement is Zn(s) + CuSO4(aq)ZnSO4(aq). Reference table J is needed when
doing single replacement.
Double replacement is a reaction when an element in a compound replaces
another element in a compound. A formula for double replacement is AB+CDAD+CB.
An example of double replacement is Pb(NO3)2+2KI2K(NO3)+Pbl2.