Final answer:
The elements “C” and “F” belong to the noble gases, which are very unreactive. The element “C”, being a noble gas, is the least reactive, and “B” and “E” would likely form an ionic bond since they are from the alkaline earth metals and halogens, respectively.
Step-by-step explanation:
i) The group of elements to which “C” and “F” belong is called the noble gases. These elements are known for their lack of reactivity due to their full valence electron shells.
ii) The letter that represents the least reactive element would be “C”. This is because noble gases like “C” are very unreactive as their outermost energy levels are full, making them stable and inert.
iii) When “B” and “E” react, they are likely to form an ionic bond. This is because “B” is likely a metal from the alkaline earth metals with a tendency to lose electrons, and “E” is likely a non-metal from the halogens that has a high electronegativity and a propensity to gain electrons. Hence, “B” would donate electrons to “E”, leading to an ionic bond.
iv) An element “G” in the third period of the periodic table that forms a G-3 ion would be located in group 16 (chalcogens). This group contains elements that typically form ions with a -2 charge; thus, the element with a -3 charge would be an anomaly, potentially indicating a significant gain of electrons or an error in the given information.