TAKS Problem
Sheets of ice containing mostly pure
water can be formed by decreasing the
temperature of saltwater. Which of
these best describes this change?
F) Chemical change
G) Physical change
H) Nuclear change
I )Atomic change
ChemCatalyst
• What do you think happened to the
copper powder in the copper cycle
experiment when it was mixed with the
Nitric Acid (H2NO3(aq))?
Model of Nitric
Acid
What Goes Around Comes
Around (Part II)
Steps of the Copper Cycle.
Step 1
Colorless nitric acid is added to solid orangebrown copper powder, resulting in a bluegreen solution, a brown gas, and liquid
water.
HNO3(aq) is added to Cu(s), resulting in
Cu(NO3)2 (aq) and NO2(g), and H2O(l).
Step 2
Clear colorless, sodium hydroxide solution is
added to the blue-green solution, resulting in
clumps of dark blue solid and clear,
colorless sodium nitrate solution.
NaOH(aq) is added to Cu(NO3)2(aq), resulting
in Cu(OH)2(s) and NaNO3(aq).
Copper Nitrate (aq)
Step 3
The dark blue clumps are heated, resulting in a
black solid (sludge…poop looking stuff you
guys poured through the filter paper…) and
liquid water.
Cu(OH)2(s) is heated, resulting in CuO(s), and
H2O(l).
Copper Oxide (s)
Step 4
Clear, colorless sulfuric acid is added to
the black solid, resulting in a clear blue
solution and liquid water.
H2SO4(aq) is added to CuO(s), resulting
in CuSO4(aq), and H2O(l).
Model of Sulfuric
Acid
Step 5
Solid, silver gray zinc is added to the
clear blue solution, resulting in a
brownish powder, and clear, colorless
zinc sulfate solution.
Zn(s) is added to CuSO4(aq), resulting in
Cu(s), and ZnSO4(aq).
Zinc Sulfate (solid)
Procedure
Symbol of
Chemical Added
Observations
Formula and
Name of
Copper
Compound
What
happened to
the Copper?
Got a sample
of copper
Cu(s)
Orange, Brown
granules
Cu(s) solid
copper granules
Nothing Yet…
Added Nitric
Acid
HNO3(aq)
Bubbles formed,
brownish gas released,
blue-green solution
formed
Cu(NO3)2(aq)
aqueous copper
nitrate
Copper is part
of the Copper
Nitrate.
Added sodium
Hydroxide
NaOH(aq)
Clumpy, blue solid
formed.
Cu(OH)2 (s)
Copper
Hydroxide
Copper is part
of the Copper
Hydroxide.
Added Heat
(removes
water)
N/A
Clumps turned
blackish, and cloudy
(Poop looking stuff…)
CuO (aq)
Solid Copper
Oxide
Copper is part
of the Copper
Oxide.
Added
Sulfuric Acid
H2SO4(s)
Clear blue solution
formed
CuSO4(aq)
Copper Sulfate
Copper is in the
copper sulfate.
Added Zinc
Zn(s)
Bubbles formed,
chunks of orangebrown solid appeared,
zinc turned black and
disappeared.
Cu(s) Solid
Copper
Copper is a
solid again, by
itself.
Part 2 Track the Copper.
Making Sense (10 min)
• No Talking…just writing.
• Describe what happened to the copper
throughout this experiment. Be
specific…