1. The horizontal rows in a periodic table are called   Atomic Structures   Lanthanides   Groups   Periods   Hint Half-n-half Clue   2. Elements in the modern periodic table are arranged on the basis of their   Atomic Mass   Chemical Symbols alphabetically   Boiling Point   Atomic Number   Half-n-half Clue   3. The Law of Octaves was given by   Mendeleev   John Newlands   Dobereiner   Bohr   Half-n-half Clue   4. The vertical rows in a periodic table are called   Groups   Periods   Noble Gases   Alkali Metals   Half-n-half Clue   5. The element with atomic number 6 is   Boron   Neon   Carbon   Oxygen   Half-n-half Clue   6. The least reactive elements of the periodic table are   Transition Metals   Alkaline Earth Metals   Noble Gases   Alkali Metals   Half-n-half Clue   7. Mercury is a   Metal   Noble Gas   Lanthanide   Non metal   Half-n-half Clue