Science at Hogwarts:
a little magic show
Presentation for
NSTA Minneapolis
Regional Conference
October 30, 2009
Jane Snell Copes
Science Outside the Box
Photo by Larry Copes
A Handful of Flames
“There was a soft,
crackling noise, and
a shivering light filled
the compartment.
Professor Lupin
appeared to be
holding a handful of
Harry Potter and the
Prisoner of Azkaban,
page 83
Flash Paper
• Flash paper is cellulose nitrate,
also called guncotton.
• It’s made by dissolving the lignin
out of paper or cotton with nitric
and sulfuric acids.
• Buy flash paper at a magic shop.
Let it dry before using.
• Toss it high and LET GO OF IT!
• Flash paper burns so completely
because what remains of the
paper contains enough oxygen
to convert it to gaseous
Photo: American Chemical Society
Fire in a Jam Jar
“The day before Harry’ s first Quidditch
match t he three of them were out in the
freezing courtyard during break, and
Hermione had conjured them up a
blue fire that could be c arried around in a
jam jar.”
Harry Potter and the Sorcerer’ s Stone,
page 181
• a gel of saturated
aqueous calcium acetate
solution and 95% ethanol
(a.k.a. Sterno) makes the
portable fire
• 1 part calcium acetate
solution to 6 parts alcohol
• alcohol flames are nearly
colorless; add salts to
change the fire’s color
Photo by Jane Copes
Colored Flames
“He took a pinch of glittering powder out of the
flowerpot, stepped up to the fire, and
threw the powder into the flames. With a
roar, the fire turned emerald green and
rose higher than Fred, who stepped right
into it, shouted ‘Diagon Alley!’ and
Harry Potter and the Chamber of Secrets,
page 47
• boric acid H3BO3 makes fine
green flames
• alkali metal salts have
distinctive flame colors
• highway flares and fireworks
rely on electronic transitions
of their constituent elements
• emission spectra of stars
(including our Sun) tell us
what elements are present
Photo: American Chemical Society
Advanced Colored Flames
¥ A good choice for outdoor purple flames: iodine
mixed with zinc dust and accelerators
¥ Just canΥt do the black flames . . . sorry!
“They stepped over the
threshold, and immediately a
fire sprang up behind them
in the doorway. It wasn’t an
ordinary fire either; it was
purple. At the same instant,
black flames shot up in the
doorway leading onward.
They were trapped!”
Harry Potter and the Sorcerer’s
Stone, pages 284-285
Photo: American Chemical Society
The Put-Outer or Deluminator
Photo: American Chemical Society
A Useful Little Device . . .
“[Dumbledore] found what
he was looking for in his
inside pocket . . . . He
flicked it open, held it up
in the air, and clicked it.
The nearest street lamp
went out with a little pop.”
Harry Potter and the
Sorcerer’s Stone, p. 9
SOMEthing does NOthing
• Carbon dioxide from
subliming dry ice puts
out flames nicely
• CO2 doesn’t burn
because it’s already
oxidized as far as
• Even without the water
vapor fog, CO2
deluminates flames
Photo by Jane Copes
Thickening Potion
“They had Potions that
afternoon, which was an
unqualified disaster. Try as
Harry might, he couldn’t
get his Confusing
Concoction to thicken.”
Harry Potter and the
Prisoner of Azkaban, page
Photo: American Chemical Society
Double Duty Powder!
• sodium polyacrylate absorbs
about 800 times its weight of
• also known as Water Lock, it’s
used in potting soils and
disposable diapers
• table salt is the “antidote” to
break the gel
• same polymer, but “folded”
makes InstaSnow
• Find both at
Photo: American Chemical Society
Crystal Ball
”Together they climbed the ladder into
the dim, stifling tower room.
Glowing on every little table was a
crystal ball full of pearly white
Harry Potter and the Prisoner of
Azkaban, page 296
Photo by David Roy
Crystal Ball
• You need bubble solution, a
container with a smooth lip,
and Bubble Fur (polar
• dry ice sublimes rapidly in
warm water, producing
clouds of water vapor and
carbon dioxide
• a film of bubble solution
expands quite nicely from
the CO2 pressure
• Try the “teacup” version for
each student
Photo by David Roy
Bat Breath
• Bromthymol Blue
indicator is yellow in
acid, blue in base
• We all have CO2 in
exhaled breath
• Add NaHCO3
(baking soda) to
keep the indicator
Photo by Larry Copes
Hagrid’s Toothpaste
• Elephant’s
Toothpaste uses
30% hydrogen
peroxide + KI or NaI
and a little dish soap
• “Teacup” version
uses 3% drugstore
peroxide and dry
Photo: American Chemical Society
The Witch Eats the Pumpkin
• Iodine Clock Reaction
• IO3- + reducing agent (S2O52) + starch  I• potassium iodate + sodium
meta-bisulfite + food
coloring  iodide
• I- + intermediate  delays
production of free I• When intermediate is used
up, I- reacts with starch 
• vary volume of one solution
to make different times
Photo by Jane Copes
Exploding Pillow -orAutomatic Alarm Clock
• You need a freezer
weight, quart size,
single zipper bag
• A little dry ice + water
• Use goggles and hold
the bag firmly by the
• Re-seal for Snooze
• For George and Fred
(of blessed memory)
Weasley’s Joke Shop
Does it ruin the magic to
unravel the science?
“You are here to learn
the subtle science
and exact art of
Harry Potter and the
Sorcerer’s Stone, page
Photo by Larry Copes
Contact Professor Sepoc
Jane Snell Copes
Science Outside the Box
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Photo by Larry Copes