1. Physical & Chemical Properties of Matter

2. Physical Properties Physical property – any characteristic that can be observed without changing the composition of the substance Physical property – any characteristic that can be observed without changing the composition of the substance

3. Examples of Physical Properties Viscosity – a liquids resistance to flowing Viscosity – a liquids resistance to flowing High viscosity = thicker, slower flow High viscosity = thicker, slower flow Conductivity – ability to allow heat to flow Conductivity – ability to allow heat to flow Metals – high conductivity Metals – high conductivity Nonmetals – low conductivity Nonmetals – low conductivity Malleability – ability to be shaped with a hammer Malleability – ability to be shaped with a hammer Metals = malleable Metals = malleable Nonmetals = nonmalleable (brittle) Nonmetals = nonmalleable (brittle) Hardness Hardness

4. Examples, cont. Melting point – temperature at which a solid changes into a liquid (Still same substance) Melting point – temperature at which a solid changes into a liquid (Still same substance) Boiling point – temperature at which a liquid changes to a gas (Still same substance) Boiling point – temperature at which a liquid changes to a gas (Still same substance) Density = mass/volume (“heavy” vs “light”) Density = mass/volume (“heavy” vs “light”)

5. Using Physical Properties Used to identify unknown materials Used to identify unknown materials Ex: used in forensics to solve crimes Ex: used in forensics to solve crimes Used to choose appropriate material for a job Used to choose appropriate material for a job Used to separate mixtures Used to separate mixtures Filtration – separates materials based on particle size (best with heterogeneous mixtures) Filtration – separates materials based on particle size (best with heterogeneous mixtures) Distillation – separate solutions based on boiling points Distillation – separate solutions based on boiling points

6. Chemical Properties Chemical property – produces a change in the composition of the matter Chemical property – produces a change in the composition of the matter

7. Chemical Properties Flammability – material’s ability to burn in the presence of oxygen Flammability – material’s ability to burn in the presence of oxygen Reactivity – ability to combine chemically with another substance Reactivity – ability to combine chemically with another substance

8. Recognizing Chemical Changes A change in color (brief video) A change in color (brief video)brief videobrief video Production of a gas (bubbles video) Production of a gas (bubbles video)bubbles videobubbles video Formation of a precipitate (brief precipitation video) Formation of a precipitate (brief precipitation video)brief precipitation videobrief precipitation video Precipitate – a solid that forms and separates from a liquid Precipitate – a solid that forms and separates from a liquid

9. Physical vs Chemical Change Physical change – occurs when some properties of a material changes, but substances in the material stays the same Physical change – occurs when some properties of a material changes, but substances in the material stays the same Example: melting of ice Example: melting of ice Chemical change – substance reacts and forms a new substance Chemical change – substance reacts and forms a new substance Example: rusting of a nail Example: rusting of a nail