The Chemical Bond
|The periodic table is an arrangement of the chemical elements ordered by atomic number in columns and rows (groups and periods). The design of the periodic table reflects the observation that many properties of the chemical elements are periodic functions of their atomic number. The periodic table is arranged so as to emphasize these periodic properties. In concert with an atom's valence shell configuration, the periodic properties of an element provide you with a thumbnail picture of its tendencies, allowing you to predict how it will behave in different contexts. The periodic properties are atomic radius, ionization energy, electron affinity and electronegativity.|
Only rarely to questions appear on the MCAT that ask you directly about periodic properties, but like so many of these early chapters, the material is fundamental to much else which comes later. Of the periodic properties, the electronegativity is especially crucial, although all of them are important. Considering the electronegativity difference between bonded atoms is the first step to assigning bond polarity. Understanding bond polarity is necessary for predicting intermolecular forces, solubility relationships or assigning oxidation numbers, for example.