Chemical & physical properties8th Grade Science

Everything is made of chemicals. There are 92 natural chemicals or elements. They are arranged on the periodic table. Each element is composed of extremely small particals called atoms.

All atoms of a given element are identical. Atoms of different elements have different properties. Each chemical has predictable properties that distinguish or separate it from other chemicals.

The properties of matter can be grouped into two categories: physical and chemical properties.

Physical properties... Describe what a substance is like or it’s ability to change in some way but it still stays the same molecule.

• Examples:

color

density

odor

melting point

boiling point

hardness

• What are some physical properties of vinegar?

smell its a liquid clear taste bitter

Chemical properties...

describe an object/substances’ ability to change into something new. We use these properties to distinguish chemicals from one another.

Ex: Flammability & Reactivity

•Some examples of chemical properties are...

paper burns

iron rusts

silver doesn’t react w/water

nitrogen doesn’t burn

•In each of these, the substances chemical property is its tendency to:

react

tarnishcorrode Explode(bubbles,Smell)

Physical vs. chemical properties

• WoodPhysical Property:

grainy texture

Chemical Property

•Flammable

PHYSICAL VS. CHEMICAL PROPERTIES

Baking SodaPhysical Property:

white powder

Chemical Property

•reacts with vinegar to produce bubbles

Chemical vs. physical properties

IronPhysical Property:

Malleable (able to be shaped)

Chemical Property

•Reacts with oxygen to form rust