Introduction to Matter Chapter 1 Introduction to Matter

Vocabulary Matter Chemistry Solution Anything that has mass and takes up space Chemistry Study of the properties of matter and how matter changes Solution Single kind of matter that is pure, meaning it always has the same makeup or composition and a set of properties

Elements/Compounds Originally Empedocles said that matter was made up of air, earth, fire and water All matter made of atoms or the basic particle from which elements are made. Positively charge nucleus Negatively charged electron cloud Chemical bond-force of attraction that holds two atoms together Molecules-groups of two or more atoms held together by chemical bonds Chemical formula-shows the elements and the ratio of atoms Ex: CO2

Mixtures Made of two or more substances (elements, compounds or both) that are together in the same place but are not chemically combined Each substance keeps its individual properties and are not in a set ratio Heterogenous mixture-see the different parts Ex: salad Homogeneous mixture-evenly mixed so that you can’t see the individual parts Ex: sugar and water (solution) or air Can separate using a magnet, filtering a mixture, and distilling a liquid solution

Properties Physical properties Chemical properties Characteristic of a pure substance that can be observed without changing it into another substance Hardness Texture Color State of matter Luster Ability to conduct heat and electricity Flexibility Shape Density Chemical properties Characteristic of a pure substance that describes its ability to change into different substances Burning or flammability Ability to react (rust) New substances with new properties produced Ex: yeast release gas to cause bread to rise

Changes in Matter Physical change-change that alters the from or appearance of matter but does not make any substance in the matter into different substance Changes in state, shape or form Methods of separating mixtures Chemical change-change in matter that produces one or more new substances Produces a new substance with properties different from those of original substance or produces heat Examples: Combustion Electrolysis Oxidation tarnishing

Matter and Thermal Energy Law of Conservation of Mass-matter is not created or destroyed in any chemical or physical change Review: Temperature Thermal energy Endothermic change-energy is taken in or absorbed Ex: when ice melts Exothermic change-energy is released Ex: combustion

Density Mass-amount of matter Volume-amount of space Density SI-kilogram Volume-amount of space SI-liter, milliliter, and cubic centimeter Volume=length x width x height Density SI-g/cm3 Floating or sinking