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What is the oxidation state of chlorine in Cl2O7? (a) -2, (b) +7, (c) -1, (d) +1
By BYJU'S Exam Prep
Updated on: September 25th, 2023
The oxidation state of chlorine in Cl2O7 is +7. The number of charges (positive or negative) assigned to an atom in a molecule or ion in accordance with a set of arbitrary principles determines the oxidation number/oxidation state of that element in a compound.
Table of content
Rules for Assigning Oxidation Number
- The monatomic ion’s oxidation number and charge are the same. For instance:
- Oxidation states of Li+, Ca2+ and Al3+ are +1, +2 and +3 respectively.
- The oxidation state of Cl- and SO42- are -1 and -2 respectively.
- With the exception of ionic hydrides, hydrogen has a +1 oxidation state in all compounds (-1 oxidation state).
- The oxygen oxidation state in a compound is -2, with the exception of peroxides, which are -1.
- Alkaline earth metals (Be, Mg, etc.) have +2 oxidation states, but alkali metals (Li, Na, K, etc.) always have +1 oxidation states.
Calculations:
To find:-
Oxidation number of chlorine in Cl2O7
Let the oxidation number of Chlorine (Cl) in Cl2O7 be x.
Based on the above rules,
2x + 7× (-2) = 0
or, 2x -14 = 0
or, x = +7.
Hence, the oxidation state of chlorine in Cl2O7 is +7.
Summary:
What is the oxidation state of chlorine in Cl2O7? (a) -2, (b) +7, (c) -1, (d) +1
+7 is the oxidation state of chlorine in Cl2O7. All elements in their free form have an oxidation number of zero. Fluorine, the most electronegative element, has an oxidation number of -1 in every molecule.