Chemical Chemical Change Change aka aka Chemical Reactions Chemical Reactions
Jan 03, 2016
Chemical Chemical
ChangeChange
akaaka
Chemical Reactions
Chemical Reactions
Concept of ChangeConcept of Change
Change Change
an act of altering a an act of altering a substancesubstance
Phys
ical C
hange
Phys
ical C
hange
A change that occurs A change that occurs which which does not does not change the identity of change the identity of the substancethe substance
Sig
ns
of
a
Sig
ns
of
a
Phys
ical C
hange
Phys
ical C
hange Melting Ice
Melting Ice Freezing Kool-aid
Freezing Kool-aid Tearing paper
Tearing paperBoiling water
Boiling water
Chem
ical
Chem
ical
Changes
Changes
A change that occurs A change that occurs causing the identity of causing the identity of the substance to the substance to changechange
New substance is New substance is formedformed
Has different Has different propertiesproperties
Mass does not change Mass does not change (Law of Conservation (Law of Conservation of Matter)of Matter)
Indicators of a
Indicators of a Chemical Chemical ChangeChange
Chem
ical
Chem
ical
Change
Change
Light given offLight given off
Chem
ical
Chem
ical
Change
Change
Presence Presence of hotof hot
Presence Presence of coldof cold
Chem
ical
Chem
ical
Change
Change
Gas producedGas produced
bubbling or bubbling or fizzingfizzing
Chem
ical
Chem
ical
Change
Change
Solid Solid precipitateprecipitate
Chem
ical
Chem
ical
Change
Change
Color changeColor change
Chem
ical
Chem
ical
Change
Change
Odor given offOdor given off
Pewwwww!Pewwwww!
Chem
ical
Chem
ical
Change
Change
Smoke producedSmoke produced
Is it a chemical Is it a chemical change?change?
Decide if it is physical or chemicalDecide if it is physical or chemical
Then tell your reasonThen tell your reason
Sm
oke
, colo
r
Sm
oke
, colo
r change
change
and a
tem
pera
ture
and a
tem
pera
ture
change
changeA forest fire destroys
A forest fire destroys
acres of land. There is
acres of land. There is
a lot of smoke, and the
a lot of smoke, and the
trees turn to charcoal.
trees turn to charcoal.
ChemicalChemical
Wate
r turn
s bro
wn b
eca
use
Wate
r turn
s bro
wn b
eca
use
the co
coa is b
row
n
the co
coa is b
row
nWhen making hot
When making hot
cocoa, clear water
cocoa, clear water
turns brown when you
turns brown when you
mix the cocoa in
mix the cocoa in
PhysicalPhysical
no n
ew
substa
nce
form
ed
no n
ew
substa
nce
form
ed
(meltin
g(m
eltin
g ))
Ice cream melts after it
Ice cream melts after it
falls on the ground
falls on the ground
PhysicalPhysical
No n
ew
substa
nce
has
No n
ew
substa
nce
has
form
ed
form
ed
(condensa
tion)
(condensa
tion)
On a hot day water
On a hot day water
forms on the outside of
forms on the outside of
a cold glass of water
a cold glass of water
PhysicalPhysical
Colo
r change
Colo
r change
A raw egg gets cooked
A raw egg gets cooked
ChemicalChemical
Gas fo
rmatio
n
Gas fo
rmatio
nWhen Alka Seltzer is
When Alka Seltzer is
dropped into water it fizzes.
dropped into water it fizzes.
ChemicalChemical
the p
aper is ch
angin
g
the p
aper is ch
angin
g
colo
r beca
use
the cra
yon
colo
r beca
use
the cra
yon
is red.
is red.
Red crayon changes
Red crayon changes
w
hite paper to red
white paper to red
PhysicalPhysical
The b
ubble
s were
alre
ady
The b
ubble
s were
alre
ady
there
, just u
nder p
ressu
re in
there
, just u
nder p
ressu
re in
the b
ottle
the b
ottle
Soda fizzes, and bubbles
Soda fizzes, and bubbles
as you pour it in a glass
as you pour it in a glass
PhysicalPhysical
Colo
r change a
nd
Colo
r change a
nd
tem
pera
ture
change
tem
pera
ture
changeWhen you crack a glow stick,
When you crack a glow stick,
hydrogen peroxide mixes with
hydrogen peroxide mixes with
other chemicals, causing it to
other chemicals, causing it to
glow and warm up.
glow and warm up.
ChemicalChemical
Vid
eo t
ime
Vid
eo t
ime
Bill Nye