Download Matter Physical Changes Chemical Changes Elements and the

Matter Physical Changes Chemical Changes Elements and the Periodic Table Everything in the universe is made of matter. A physical change occurs when matter changes form but not its identity. Changes in shape, size, or state (phase) are physical changes. A chemical change (aka a chemical reaction) occurs when matter combines or breaks apart to make something new. The Periodic Table is a tool for organizing and understanding the elements. Matter can be classified by physical and chemical characteristics. Matter can exist in 3 main states (solid, liquid, or gas) and can change state* (phase) if energy is added or subtracted. Matter can be identified by analyzing characteristic properties (properties that never change). In solids, molecules are tightly arranged. Solids have a definite volume and a definite shape. Acid/base reactions are one special type of chemical reaction. Acids and Bases can neutralize each other. Solubility, Density, and pH are characteristic properties. In liquids, molecules are not as tightly arranged. Liquids have a definite volume but no definite shape. Acids taste sour and corrode most The families (vertical groups) in metals. the Periodic Table have the same Their pH ranges from 0‐6. number of valence electrons and The strongest acid has a pH of 0. therefore similar characteristics. Chemical reactions usually can be Atoms are the smallest particle of identified by indicators: color an element and are made of change, gas production, proton, electrons, and neutrons. temperature change, or formation of a precipitate. The temperature at which a change Bases taste bitter, have a slippery in the state* of matter occurs is a (oily) feel, and corrode most In gasses, molecules are loosely metals. characteristic property. arranged. Gasses have no definite Their pH ranges from 8‐14. [i.e. freezing, melting, volume and no definite shape. The strongest base has a pH of condensation, boiling/vaporization 14. points] Flammability, Hardness, Magnetism, and Radioactivity are characteristic properties. The pH of distilled water is neutral – 7. The number of protons (the atomic number) determines the identity of an atom. All of the elements in a period (row) have the same number of atomic orbitals (shells) from 1 through a maximum of 7. The three main groups of elements (metals, metalloids, and non‐metals) have similar locations on the Periodic Table and therefore have similar properties.