Presentation on theme: "The Classification of Matter. PURE SUBSTANCE Something that cannot be broken down into simpler matter using only physical methods. There are two kinds."— Presentation transcript:
Most elements are built of individual atoms (ex. Fe, Cu): But a few gaseous elements exist as diatomic molecules. Diatomic Gases Hydrogen H 2 Nitrogen N 2 Oxygen O 2 Fluorine F 2 Chlorine Cl 2 Bromine Br 2 Iodine I 2
COMPOUNDS Are pure substances that are composed of atoms of 2 or more different elements, chemically bonded to one another due to the transfer or sharing of valence electrons. Compounds can only be made or broken down by chemical reactions.
COMPOUNDS Have exact or definite compositions given by a chemical formula (ex. NaCl or H 2 O). We call the building blocks of compounds molecules!
COMPOUNDS The properties of compounds are very different from the properties of the elements that make them up!
MIXTURES A mixture is something that CAN be broken down into simpler materials using physical methods, not chemical reactions. Each part of a mixture keeps its own identity! There are 3 possible types of mixtures: 1)Element + Another Element 2)Compound + Another Compound 3)Element + Compound
MIXTURES There are two types of mixtures: a)Homogeneous- The parts are distributed evenly (dissolved) at the particle level. Every sample is the same. Examples: Salt water; syrup; air; brass.
MIXTURES Homogeneous mixtures are also called solutions. Homogeneous mixtures of solidmetallic atoms are called alloys.
MIXTURES b) Heterogeneous- The parts are not evenly mixed, to the eye and even under a microscope. Every sample is different! Examples: Spaghetti and Meatballs; water + oil mixture, blood.
We learned that the properties of compounds are TOTALLY DIFFERENT from the properties of the elements that make them up. By contrast, the properties of mixtures ARE very much related to the properties of the substances that make the mixtures up. Properties of Saltwater
Matter Flowchart MATTER Can it be physically separated? Homogeneous Mixture Solutions + Alloys Heterogeneous MixtureCompoundElement MIXTUREPURE SUBSTANCE yesno Can it be chemically decomposed? noyes Is the composition uniform? noyes
Methods of Mixture Separation 1)Mechanical Separation
Methods of Mixture Separation 2) Magnetic Separation
Methods of Mixture Separation 3) Density Separation: More dense components sink.