Chemical and Physical Changes

9 Science

Definitions

Chemical Change- A change where new particles are formed and are usually not reversible

Physical Change- a change which does not alter the identity of the sample ( no new substance is formed) and the change can be reversed.

Observations (things you can expect to see which accompany a chemical change)

Bubbles New color Heat or light given off Precipitate forms * new substance forms *it’s not reversible

Observations for a Physical Change

No new substance formed Can be reversed

Chemical/Physical Property

Chemical Property- any property which describes how a substance reacts with another substance

Physical Property- a property which can be observed/ measured without forming a new substance

** these can be either Qualitative or Quantitative

Qualitative

Describes but not measured Size Color Taste Smell Texture Ductile (stretch) Malleable (flattened, shaped)

Quantitative

Can be measured Melting point Boiling point Density, etc.

Terms:

Solute- substance which is dissolved ( in the smallest amount)

Solvent- the substance that does the dissolving ( in the largest amount)

Define- element and compound

Make 2 headings (Chemical and Physical) and place the following words under the appropriate heading:

Respiration * cooking meat * eroding soil

Freezing * ice melting * iron rusting

Burning paper * steaming rice * evaporating

Wearing down an eraser * grinding wheat * frying bacon

Wood rotting * building a snowman *chopping logs

Bending iron * slicing a cake *etching glass with acid to

Fireworks * breaking glass make stained glass

Burning logs * car burning gas

Baking a cake * digesting dinner

Condensing * drying hair