1 Properties of Matter S. Staron 2-11

2 Matter u Matter is anything that has mass and volume u Everything is made of matter

3 What are properties? u Characteristics used to describe an object (size, shape & color).

4 What is a physical property? u Physical properties are those that can be observed without changing the identity of the substance

Intensive and Extensive u Intensive properties such as density, color, and boiling point do not depend on the size of the sample of matter and can be used to identify substances. u Extensive properties such as mass and volume do depend on the quantity of the sample. 5

6 Physical properties of matter include:

Conductivity u Conductivity is the ability to conduct electricity and heat. u Copper wire is conductive. u Dry string isn’t. 7

Density u The density of a substance is found by dividing the mass by the volume. u D = M/V u The density of water is 1.0 g/ml 8

9 Astronomy trivia fact! u The planet Saturn has a density of less than 1.0 g/ml. If there was an ocean big enough to hold it, it would float!

10 What is specific gravity? u Specific gravity is a comparison of the density of a substance to the density of water S. G. = Density of substance Density of H 2 O

Hardness u Hardness relates to the resistance of a substance to being scratched by another substance. u Diamonds are very hard. u Talc is soft. 11

Malleability u Malleability refers to how bendable a substance is, or its ability to be hammered without shattering. u Leather and silver are malleable. u Chalk and countertops are not malleable. 12

Ductility u Ductility refers to how easily the substance can be drawn into a wire. u Copper is ductile. u Paper & cement are not. 13

Viscosity u Viscosity refers to how thick a liquid is, or the resistance of a liquid to flow. u Honey is very viscous. u Water is not viscous at all. 14

Mass u The mass of something is how much matter is contained in it. u In the metric system, we measure mass in grams (g) or kilograms (kg). 15

Matter Changes u All matter, regardless of state, undergoes physical and chemical changes. These changes can be microscopic or macroscopic. 16

17 What is a physical change? u Physical changes involve the changing of physical properties u The type of matter remains the same

18 Examples of Physical Changes u A change of: u Color (mixing paint) u Shape (crumpled paper) u Phase (solid to liquid) u Texture (rough to smooth)

19 Phase changes are physical changes u Adding or removing energy (heat) from matter results in phase changes. u Phase changes involve a change in volume, but mass remains constant

20 Six Phase Changes u The six phase changes are: u melting/freezing u (between solid and liquid) u vaporization/condensation u (between liquid and gas) u deposition/sublimation u (between solid and gas)

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22 Physical Behavior of Liquids: Cohesion & Adhesion u Cohesion is the force of attraction between LIKE particles u Adhesion is the force of attraction between UNLIKE particles

23 Physical Behavior of Liquids: Surface tension u Surface tension is the tendency of particles to pull together at the surface of a liquid due to cohesion.

Surface Tension Examples 24 Water striderPaper clip Mercury

Chemical Properties u Chemical properties describe the way a substance changes, or reacts to form other substances. 25

Chemical properties of matter u Flammability u The ability of a substance to burn u Wood is flammable, concrete isn’t. u Reactivity u The ability of a substance to combine with other substances u Chlorine is very reactive, Neon isn’t. 26

What is a chemical change? u A chemical change: Produces new substances u May be noted by: u A change in color (silver tarnishing) u Bubbles formed u Precipitate formed u Temperature change (sometimes) 27

Different Properties of Hg, O 2 and HgO 28