Chemistry 112 Elements and Compounds

What’s the difference?  Elements are the simplest form of matter.  They have a unique set of properties  A compound is a substance that contains two or more elements chemically combined in a fixed proportion.  Compounds cannot be separated by physical means, only chemical.  Elements cannot.

How do you breakdown a chemical compound?  Chemical changes are required for the breakdown of chemical compounds.  Chemical changes give products that are chemically different from the reactants.  How are compound sentences like chemical compounds?

Substances and Mixtures  If the composition of the material is fixed, the material is a substance.  Elements and compounds.  If the composition of the material varies, the material is a mixture.  Homogeneous and heterogeneous mixtures.

Symbols and Formulas  Chemical symbols are used to represent elements.  Na, O, S, Au  and chemical formulas are used to represent compounds.  NaCl, H 2 O, CO 2, CaCO 3

To be completed:  Questions 20 – 27, pg. 52