Lesson 1-4

How are Chemical and Physical Properties

Used?

I. Separating MixturesA. Physical Properties

1. used to separate mixtures

2. Ex. of separate mixtures by physical

properties:a. Picking out grapes in

a fruit saladb. sugar/flour – sugar

dissolves in water, flour doesn’t

c. sifting sand

B. Chemical Properties 1. How a substance reacts or combines to form new substances

2. Require the substance to be changed.

a. Flammable/burnsb. Rust/changes colorc. Creates gas/bubbles formd. Changes Temperature3. Ex. Of separating mixtures using Chemical Properties:a. Copper in nature – sulfur and oxygen removed by crushing and adding chemicals

C) Chemical properties can be used to identify materials.

1. Litmus paper can be used to identify acids and bases.

a. Acids turn blue litmus paper red

b. Bases turn red litmus

paper blue.

2. Rank acids/bases on pH scale from 0 to 14

a. Acid = less than 7 (ex: OJ)

b. Base = more than 7 (ex: cleaner)

c. neutral = 7 (ex: water)

D. Ways to identify substances1. Physical Properties

a. color & texture (5 senses)b. melting pointsc. solubility (ability to

dissolve)2. Chemical Properties

a. change the substance – combine with an acid

or baseb. Flame test : different

substances burn with different colored flames.