Chapter 1: The Puzzle of Matter•Chemistry explains the structure, composition and behavior of matter.

•Matter is anything that takes up space and has mass.

•Properties of matter•Macroscopic – see with unaided eye•Microscopic – see with a microscope•Submicroscopic – need a special microscope or the use of models. •Scientific Models - used to explain observations. Based on scientific investigation and experimentation.Period at the end of a sentence =. 1 x 10 20 atoms!!!!STM - scanning tunneling microscope – study atoms

nanoscale technology

Classifying Matter

•Qualitative – made without measurement

•Quantitative – observation made with measurement, data

Pure Substance or Mixture?

•Pure – one kind of matter

•Mixture – different kinds of matter

aspirin sucrose

Mixtures - substances mixed together but not chemically combined. Example: ocean water, granite, air, blood

3 properties of mixtures:1) keep their separate identities2) the substances may be present in any amount3) the substances can be separated out by simple physical means – ex: evaporating, using a magnet, density

Heterogeneous Homogeneous

2 Types of Mixtures

Least mixed –

Ex: Concrete, oil and vinegar, blood

Well Mixed – appear to be the same throughout EX: lemonade, ocean water, air

Solutions

“Best mixed” – homogenous mixture • 2 or more substances in one physical state.

AIR – gas

Lemonade – liquid

Solid - Metal solutions are called alloys ex: brass, steel.

Stainless steel – mixture of 2 metals; chromium and iron

Brass = copper and zinc

•In a solution the substance that dissolves is called the solute and

the substance that does the dissolving is called the solvent.

Water = “Universal Solvent” When water is the solvent its known as an ‘aqueous solution’.

Elements

•A type of pure substance that cannot be broken down into simpler substances.

iron

sulfur

Compounds

•Type of pure substance that can be broken down into simpler substances.

•Compounds – 2 or more different elements bonded together.

Salt NaCl - Halite

•Formula – shows what elements are present in the compound and how many atoms of each element.

Ex: Carbon Dioxide (CO2) – one atom of carbon and 2 atoms

of oxygen

2 = subscript

Sodium Chloride (NaCl)

Water (H2O)

Ascorbic acid – C6H8O6 Vitamin C