Describing Matter Chapter 2 Section 1

Compounds All matter is made of elements, but most elements are found combined with other elements. A ______________ is a pure substance made of two or more elements chemically combined in a set ratio.

Compound A compound may be represented by a _________________, which shows the elements in the compound and ratio of atoms. H O CO HCL H SO NH C H O

Compounds When elements are chemically combined, they form compounds having properties that are different from those of the uncombined elements.

Mixtures Elements and compounds are pure substances, but most of the materials you see everyday are not. A ___________ is made of two or more substances – elements, compounds, or both – that are together in the same place but are not chemically combined.

Mixture Difference between Mixture and Compound Each substance in a mixture keeps its individual property. The parts of the mixture are not combined in a set ratio. Two Types of Mixtures 1 - __________________ 2-___________________

Mixture A heterogenous mixture is a mixture in which pure substances are unevenly distributed throughout the mixture. A homogenous mixture is a mixture in which substances are evenly distributed throughout the mixture.

Mixture In a homogenous mixture, one cannot see the different parts of the mixture. Mixed evenly A well-mixed mixture containing several compounds or substances is called a solution.

Separating Mixtures A compound can be difficult to separate into its elements because of the chemical bonds. But, a mixture is usually easy to separate into its components because each component keeps its own properties.