Pre-class Activity 1 Physical properties of matter are those properties that can be observed or measured without changing the composition of the matter. The ability of a substance to combine with or change into one or more other substances is called a chemical property Does the photograph to the right depict a physical property of water or a chemical property of water? Homework Begin work on chapter 3 homework questions

Classification of Matter Matter SubstancesMixtures Contains only one type of matter. AKA pure substances Contains more than one type of matter. Physical Change

Physical Properties of Matter Physical properties of matter are those properties that can be observed or measured without changing the composition of the matter.

Extensive vs. Intensive Properties Extensive properties are dependent on the amount of matter present Intensive properties are independent of the amount of matter present.

States of Matter (Physical Forms) StateShapeVolumeCompressibility Solid Liquid Gas Definite Indefinite Definite Indefinite Incompressible Nearly Incompressible Compressible

Chemical Properties The ability of a substance to combine with or change into one or more other substances is called a chemical property A chemical property cannot be observed without a substance undergoing a chemical change (changing into a new substance)

Physical Change A change which alters a substance without changing its composition

Pre-class Activity 9/18 What is required to separate a mixture into individual substances? A Physical Change What is the key difference between a physical change and a chemical change? During a physical change the composition of matter stays the same. The composition of a substance is altered as a result of a chemical change. Homework Be prepared for homework quiz #2 (sections ) on Friday

Mixtures Matter SubstancesMixtures Physical Change HomogeneousHeterogeneous Constant composition throughout. AKA solutions Not well blended. Individual components remain distinct

Separation Techniques Chromatography: Separates the components of mixtures (mobile phase) on the basis of the tendency of each to travel or be drawn across the surface of another material.

Separation Techniques Distillation: Separates homogeneous mixtures based on differences in boiling points.

Separation Techniques Filtration: Uses a porous barrier to separate a solid from a liquid in a heterogeneous mixture.

Separation Techniques Crystallization: A technique that results in the formation of pure solid particles of a substance from a solution containing the dissolved substance

Substances Matter CompoundsElements SubstancesMixtures Physical Change HomogeneousHeterogeneous A chemical combination of two or more different elements Chemical Change A pure substance that can not be broken down in to simpler substances by physical or chemical means

Evidence of a Chemical Reaction Change in color Change in temperature Endothermic vs. Exothermic Production of a gas Production of a precipitate Absorption of energyRelease of energy Two liquids are combined and a solid is formed

Subscript Coefficient Law of Conservation of Mass “Mass is neither created or destroyed in a chemical reaction, it is conserved” 47g + 32g 79g

Compounds Law of Definite Proportions: Elements combine in definite proportions by mass. The percent by mass of each element in a compound will be the same regardless of the quantity of the compound.

Compounds Law of Multiple Proportions: When different compounds are formed from the same elements, different masses of one element combine with the same relative mass of the other element in small whole numbers. FeBr 2 and FeBr 3