What are the physical properties and chemical properties of matter?

Contributed by:
A physical property is a property that is measurable, whose value describes the physical state. a chemical property is a characteristic of a particular substance that can be observed in a chemical reaction.
1. Physical and Chemical Properties
2. A physical property is a characteristic of a
material that can be observed or measured
without changing the composition of the
• Viscosity • Hardness
• Conductivity • Melting and
• Malleability Boiling point
• Density
3. Viscosity
• The resistance to flow. The thicker a liquid, the
higher the viscosity (the slower a liquid moves).
What has higher viscosity, water or honey?
• Viscosity usually decreases when a liquid is heated.
What is more viscous, oil in a hot wok or oil in a cold wok?
4. Conductivity
• The ability to allow heat to flow.
• Metals are good conductors; they have a high
conductivity. (they also conduct electricity well)
• Wood is a poor conductor.
Which spoon would you use to stir boiling water and pasta?
5. Malleability
• The ability of a solid to be hammered without
• Most metals are malleable. Solids that shatter when
struck are called brittle.
What is more malleable, gold or glass?
6. Hardness
• Hardness is the ability to scratch a material. Hard
materials can scratch other softer materials.
• Many grinding wheels contain diamond particles
because diamond is a very hard material.
In order to sharpen this
hunting knife, how hard
must the grinding stone
7. Melting and Boiling Points
• Melting point – the temperature at
which a substance turns from a solid to
a liquid.
• Boiling point – the temperature at which
a substance turns from a liquid to a gas.
8. Density
• The ratio of mass of a substance to its volume (D =
• Density can be used to test the purity of a substance.
(remember the King and his crown story)
The coin on the left is pure silver. The coin on the
right is fake. How could you prove that?
9. What can you do with the knowledge
about a material’s physical properties?
1. They help to identify a material by comparing the
results to known materials.
(Ex.- finding red paint chips at a crime scene and
comparing them to a data base of known car paint)
2. They help you to choose one type of material over
another to perform a task.
(Ex.- you would not want to construct a shelter out of
cellulose packing peanuts)
10. 3. They can help to separate mixtures by:
The process that separates materials based on the size of
the particles.
(Ex.- drip method to brewing coffee separates liquid from
coffee grounds)
The process that separates substances in a solution based
on their boiling points.
(Ex.- Boiling seawater to evaporate and collect the fresh
water for drinking. Sea salts are left behind)
11. How do you recognize physical changes?
• When some of the properties of the material change
but the substances in the material remain the same.
Melting butter Slicing a tomato
Crumpling paper Cutting hair
• Some physical changes can be undone, some cannot.
12. Chemical Properties
13. What is a chemical property?
• The ability to produce a change in the
composition of matter.
• They can be observed only when one substance
in a sample of matter is changed into another
Ex.-whenever something is burned, that substance
becomes something completely different. The
ability to burn is a chemical property.
14. Flammability
• The ability to burn in the presence of
15. Reactivity
• How easily a substance combines chemically
with another substance.
Oxygen easily
reacts with many
other elements.
What other
element is oxygen
reacting with in
this photo?
16. How Can You Recognize Chemical Changes?
• A change in color – Ex. The green patina on an old copper roof.
• Production of a Gas – Ex. Using baking powder and water in a
cake mix. CO2 is produced which helps the cake rise.
• Formation of a Precipitate – (any solid that forms and separates
from a liquid). Ex. Adding vinegar to milk causes the proteins to
clump together.
(The Law of Conservation of Mass states that even though chemical
changes occur, matter is neither created or destroyed in the
18. Is a change in color always an
indicator of a chemical change?
19. Is the formation of a gas always
an indicator of a chemical
20. Physical v. Chemical Changes
• Before you decide whether a chemical
change has actually taken place, ask
yourself this question: Are different
substances present after the change
takes place? If not, it is a physical
change (the composition of the matter
stays the same).