A sample of matter that has definite chemical and physical properties. A sample of matter that has definite chemical and physical properties

A sample of matter that has definite chemical and physical properties.

• A sample of matter that has definite chemical and physical properties.

pure substance that cannot be separated into simpler substances by physical or chemical means.

• pure substance that cannot be separated into simpler substances by physical or chemical means.

• Pure substance composed of two or more different elements joined by chemical bonds.

• Made of elements in a specific ratio
• that is always the same
• Has a chemical formula
• Can only be separated by
• chemical means, not physically

Table Salt  NaCl (sodium chloride)

• Table Salt  NaCl (sodium chloride)

• Chalk  CaCO3 (calcium carbonate)

• Rust  FeO (iron oxide)

• Carbon Dioxide  CO2

• A combination of two or more pure substances that are not chemically combined.

• substances held together by physical forces, not chemical

• No chemical change takes place

• Each item retains its properties

• in the mixture

• They can be separated physically

Two groups:

• Two groups:

• Heterogeneous mixtures - substances that are not distributed evenly throughout the mixture; you can see the different parts
• Examples: chicken noodle soup, oil and water, orange juice with pulp and ice cubes
• Homogeneous mixtures (ALSO KNOWN AS SOLUTIONS) - substances that are evenly distributed throughout the mixture; you canNOT see the different parts
• Examples: blood, coffee, pulp-free orange juice, salt water

You will be shown a series of photos. Tell if each photo represents an item composed of an element, compound, or mixture.

• You will be shown a series of photos. Tell if each photo represents an item composed of an element, compound, or mixture.

• Review:

• An element contains just one type of atom.

• A compound contains two or more different atoms joined together.

• A mixture contains two or more different substances that are only physically joined together, not chemically.

• A mixture can contain both elements and compounds.

Rocks

• Rocks

Copper

• Copper

Jelly Beans

• Jelly Beans

Table Sugar

• Table Sugar

Tea

• Tea

Salt

• Salt

Neon Gas

• Neon Gas

Salad

• Salad

Pure Water

• Pure Water

Aluminum

• Aluminum

Lemonade

• Lemonade

Silver

• Silver

Sand

• Sand

Rocks

• Rocks

Copper

• Copper

Jelly Beans

• Jelly Beans

Table Sugar

• Table Sugar

Tea

• Tea

Salt

• Salt

Neon Gas

• Neon Gas

Salad

• Salad

Pure Water

• Pure Water

Aluminum

• Aluminum

Lemonade

• Lemonade

Silver

• Silver

Sand

• Sand