Final answer:
The oxidation states of noble gases in the given compounds are determined by balancing the negative charge contributed by oxygen and fluorine in the compounds to make the overall charge neutral.
Step-by-step explanation:
The oxidation state of a noble gas in a compound is determined by considering the oxidation states of the other atoms in the molecule. By convention, fluorine is assigned an oxidation state of -1 in all its compounds because it is the most electronegative element. Oxygen, being less electronegative than fluorine, is usually assigned an oxidation state of -2.
Let's determine the oxidation states of the noble gases in the given compounds:
XeO2F2: The oxidation state of oxygen is typically -2, and fluorine is -1. With two oxygens and two fluorines, the total charge they contribute is -6. Since the molecule is neutral, xenon must have an oxidation state of +6 to balance.
KrF2: With two fluorines, each at -1, the total negative charge is -2. To balance, krypton must have an oxidation state of +2. XeF3+: Three fluorines contribute a charge of -3, while the molecule has an overall charge of +1. Hence xenon has an oxidation state of +2.
XeO64-: Oxygen has a total charge of -2 x 6 = -12, and since the ion has a charge of -4, xenon has an oxidation state of +8. XeO3: Three oxygens contribute -6 in total, so xenon must have an oxidation state of +6.
It is important to note the general rules for assigning oxidation numbers, such as fluorine always being -1 (due to its high electronegativity) and oxygen generally being -2, except in peroxides or when bonded to more electronegative elements like fluorine.