Multiple ChoiceIn the following diagram, the element with atomic number 8 is represented by a question mark. Which element's symbol should replace the question mark?36views
Multiple ChoiceIn the periodic table, the element manganese is represented by a box containing the symbol 'Mn'. If an arrow is pointing to 'Mn', what does this symbol indicate?47views
Multiple ChoiceWhich of the following element symbols represents the element found in mercury?34views
Multiple ChoiceWhich element is in the same period as ruthenium (Ru) but has a higher atomic number than ruthenium?51views