THERE ARE MANY USEFUL RULES IN CHEMISTRY WHICH HELP US TO LEARN AND TEACH CHEMISTRY CONCEPTS EASILY. TRENDS IN THE PERIODIC TABLE OF THE ELEMENTS, RULES, SUCH AS, OCTET, MARKOVNIK OFF, SOLUBILITY, FAJANS, HÜCKEL AND HUND ARE ONLY FEW EXAMPLES OF MYRIAD COMMON RULES WHICH HAVE IMPORTANT APPLICATIONS IN UNDERSTANDING AND EXPLAINING FUNDAMENTAL CHEMISTRY CONCEPTS. IN THE SAME TIME, CHEMISTRY IS ALSO RIFE WITH TREMENDOUS NUMBER OF Exceptions (REAL AND APPARENT) WHICH LIMIT THE BROADER APPLICATIONS OF THESE RULES. IN FACT, ONE OF THE COMMON COMPLAINTS YOU HEAR A LOT FROM STUDENTS LEARNING CHEMISTRY IS THAT THERE ARE JUST SO MANY Exceptions. IT ISN’T LONG AFTER YOU LEARN ABOUT OCTET’S RULE, FOR INSTANCE, THAT YOU LEARN WHEN THIS “RULE” IS BROKEN AND THAT’S JUST ONE OF SEVERAL Exceptions THAT COME UP IN AN ELEMENTARY CHEMISTRY COURSE.THESE MANY Exceptions IN CHEMISTRY CAN BE ANNOYING FOR THE STUDENTS AS WELL AS FOR TEACHERS IF NOT TACKLED PROPERLY. ONE COMMON APPROACH TO DEAL WITH THE Exceptions IS TO SIMPLY MEMORIZE THEM, THE WAY YOU MIGHT MEMORIZE Exceptions IN LEARNING ENGLISH. WHILE A MEMORIZATION APPROACH COULD BE EFFECTIVE FOR EXAMS THAT TEST THE ABILITY TO REGURGITATE BOOK KNOWLEDGE, HOWEVER, ANY INSTRUCTOR LOOKING TO TEST PROBLEM-SOLVING ABILITY COULD EASILY DESIGN A TEST THAT WILL RENDER SUCH PURE MEMORIZATION EFFORTS INEFFECTIVE. IT MUST BE EMPHASIZED THAT BEHIND EVERY EXCEPTION IN CHEMISTRY THERE IS A DEEP REASON WHY THINGS OCCUR THE WAY THEY DO, AND THESE REASONS ILLUSTRATE DEEPER PRINCIPLES OF CHEMISTRY.WHEN APPROPRIATE AND SCIENTIFICALLY BASED EXPLANATION IS GIVEN FOR AN EXCEPTION, NOT ONLY THE EXCEPTION WILL BE NO LONGER ANNOYING BUT IT CAN BRING ABOUT CONSTRUCTIVE CHEMISTRY TEACHING. WE EXPECT THAT THE BEHAVIOR OF ATOMS AND MOLECULES CAN BE EXPLAINED ACCORDING TO CERTAIN RULES, WHEREAS, IN REALITY NATURE HAS ITS OWN RULES WHICH WE CONSIDER MANY OF THEM AS Exceptions?! ONE OF THE MANY EXAMPLES TO ILLUSTRATE THE LAST STATEMENT IS PERHAPS THE REAL AND IDEAL CRYSTALS. REAL CRYSTALS ALWAYS HAVE CERTAIN DEFECTS OR IMPERFECTIONS, AND THEREFORE, THE ARRANGEMENT OF ATOMS IN THE VOLUME OF A CRYSTAL IS FAR FROM BEING PERFECTLY REGULAR. IN ANOTHER WORD, MOST REAL MATERIALS HAVE ONE OR MORE “ERRORS IN PERFECTION” WITH DIMENSIONS ON THE ORDER OF AN ATOMIC DIAMETER TO MANY LATTICE SITES. WE ARE INTEND TO DISCUSS A NUMBER OF VERY COMMON Exceptions IN BASIC CHEMISTRY AND GIVE PROPER ACCEPTABLE EXPLANATION FOR VIOLATIONS OF SOME RULES.