Presentation on theme: "Chapter 2 Dr. C.’s AP Chemistry Lake Dallas High School Fall 2014."— Presentation transcript:
Chapter 2 Dr. C.’s AP Chemistry Lake Dallas High School Fall 2014
Law of Conservation of Mass Mass is neither created nor destroyed in a chemical reaction (it just changes form) – Burning of a candle
Law of Definite Proportion A given compound always contains exactly the same proportion of elements by mass – H 2 O
Dalton’s Atomic Theory Each element is made up of tiny particles called atoms The atoms of a given element are identical; the atoms of different elements are different in some fundamental way Chemical compounds are formed when atoms of different elements combine with each other. Chemical reactions involve reorganization of the atoms (different bonding) but the atoms are not changed.
History of Atomic Theory
Modern Atomic Structure Nucleus ( cm diameter) Electrons (avg. distance cm from nucleus) Nucleus contains: – Protons & Neutrons Nucleus accounts for almost all of the atoms mass.
Number of electrons determines the chemical properties of an atom. The number of protons determines the identity of the atom
Practice Ca Fe Fe 2+ Br -
Groups/Families have similar chemical properties Atomic Radius increases down the groups
Isotopes Same number of protons, different number of neutrons. – Dalton’s assumption that all atoms of the same element were identical in all their properties.
Which Carbon isotope is the most common/abundant? 12 C 13 C 14 C Why?
Charges on Transition Metals PbCl 2 MnO 2 CuCl ** Charges must balance each other **
Polyatomic Ions (p. 65 in your book)
Naming Ionic Compounds From Formula to Name Metal + Non-metal OR Metal + Polyatomic 1 st Name the cation. – If the cation is a transition metal its charge must be written in ( )’s. 2 nd Name the anion and change its ending to -ide OR Write full name of the polyatomic anion
Practice CoBr 2 Al 2 O 3 CaCl 2
Naming Ionic Compounds From Name to Formula Metal + Non-metal OR Metal + Polyatomic 1 st Write the symbol for the cation and its charge. 2 nd Write the symbol for the anion and its charge 3 rd Circle the charges and “cross” them to balance charges.
Practice Gallium Bromide Manganese (IV) Oxide Lead (II) Chloride Calcium hydroxide
Homework Wednesday We Will Discuss Naming Covalent Compounds and Naming Acids Work on your journal article Read pages 54 – 70 Start on Homework #2 (page ) 5, 12, 23, 24, 36, 42, 50, 56, 58, 64, 68, 72, 74, 76, 78, 80, 84, 86, 90, 94, 96, 98, 112, 120