Juliana Mendonca Lecture Notes Monday September 21 2015 Ch 2 Elements and the Periodic Table Arrangement of the Periodic Table o Periods horizontal rows of the periodic table right such as change in atomic size o Groups vertical columns of the periodic table Have periodic trends changes that occur between elements in rows from left to Elements of groups have similarities in both chemical and physical properties 18 groups from left to right and numbered accordingly Main group elements o Groups 1 2 and Groups 13 18 or a group named with an A after the number is a main group metal o Groups 3 12 or B groups are transition metals o 7 periods on the periodic table Portions of periods 6 and 7 aren t included in the row and are placed underneath the main body of the periodic table these rows are called lanthanides and actinides o Elements on the left side of the periodic table are metals and on the right side are nonmetals the middle has metalloids or semimetals with the exception of Mercury which is a liquid metal o Electronegativity the capability of an atom to draw an electron to itself from another Periodic Properties bonding pair Electronegativity increases up and to the right of the periodic table Ionic bonds atoms with great differences in their electronegativity transfer an electron or electrons from one to the other Covalent bonds atoms have almost equal levels of electronegativity and share electrons Partial ionic character when levels of electronegativity are different between atoms Polar refers to the presence of a dipole partial positive and negative negatives that result from uneven distribution of electrons Oxygen is second most electronegative element Hydrogen basically equal in electronegativity to Carbon The further apart elements are on the periodic table the greater the differences in electronegativity more ionic
View Full Document
Unlocking...