Physical and Chemical changes
Rusting Iron
Chemical change
Melting Ice
Physical change
Formation of stalagmites in a cave
Physical change
Fertilizing a lawn
Chemical change
What are the five signs or symptoms of a chemical change?
Production of an odor, change in color, change in temperature/ production of light, formation of a gas/ bubbles, and formation of a solid called a precipitate
Boiling water
Physical change
What is a chemical change?
A change of one substance into a new substance.
Breaking a tree limb
Physical change
Toasting marshmallows
Chemical change
Why is souring milk a chemical change?
Souring milk produces an odor and forms new chunks in the milk, which are signs or symptoms of a chemical change.
Burning paper
Chemical change
What is a physical change?
A change in any physical property of a substance, but not the substance itself.
Slicing a block of cheese
Physical change
The action of yeast in breadmaking
Chemical change
Erasing a pencil mark
Physical change
Salting ice on the sidewalk
Chemical change
Bleaching clothes
Chemical change
Why is bending a metal wire a physical change?
Bending a metal wire changes the shape of the wire, which is a physical property, but does not change the molecular formation of the wire/ the stuff that makes up the wire. The wire is still a wire.
Wadding up a sheet of paper
Physical change
Burning gas
Chemical change
Digesting foods
Chemical change
Chewing foods
Physical change
Evaporation of water
Physical change
Etching glass with acid
Chemical change
Crushing ice in a blender
Physical change
What are some ways to tell if a change is physical?
You can tell if a physical change is occurring by asking yourself if there is a change in color, shape, size, texture, volume, mass, and/ or density. These are physical properties and if they are changing they are physical changes.
A change from one substance into a new substance.
Chemical change
A change in any characteristic of a substance, but not the substance itself.
Physical change