Week 1

Is There A Method to the Madness?

What is Matter? 

• Anything that has mass and occupies space

Chemist view .. matter is what chemical substances are composed of

Physical Properties can be observed/measured without changing the composition of matter.  They are used to describe matter.

• Color
• Odor
• Luster (how shiny)
• Hardness (resistance to scratching)
• Malleability (ability to be pounded into thin sheets)
• Buoyancy (ability to float in a fluid)
• Viscosity (resistance to flow)
• Elasticity (ability to be stretched and return to original size)
• Density (relationship between mass and volume)

• melting/boiling/freezing point - Solid, Liquid, or Gas

Ways matter Physically Changes 

• Cutting wood
• Melting ice cream
• Boiling water
• Freezing juice for popsicles 
• Cracking an egg

* A Physical Change alters the substance without changing the composition of the substance*

Chemical Properties describes matters "potential" to undergo some chemical change or reaction. Can only be observed when the identity of the subject is changed.

• Flammability
• Reactivity
• Toxicity
• Oxidation

Ways matter Chemically Changes 

• Rusting nail
• Burning wood
• Explosion of dynamite
• Rotting food
• Baking a cake
• Cooking an egg

* A Chemical Change alters the composition of the substance, a new substance is formed*

Signs of a Chemical Change

1. Gas bubbles form (possible new odor)
2. Light, heat, or sound is given off (or absorbed)
3. Change in color
4. Formation of solid matter (precipitate) in liquid
5. Decomposition of matter