Which of the following elements show +7 oxidation state? A. Manganese B. Boron C. Carbon D. Oxygen
Hint: Oxidation is defined as the loss of electrons or we can say that increase in the oxidation state of an atom, ion or molecule while reduction can be defined as the gain of electrons or decreases in the oxidation state of any given atom, ion or molecule.
Complete answer: The oxidation number also known as oxidation state which describes the degree of oxidation i.e. loss of electrons of an atom in a chemical compound. Conceptually the oxidation state may be positive, negative or zero. Oxidation states are typically represented by integers which may be positive, zero, or negative. In some cases, the average oxidation state of an element is a fraction. The substance which donates electrons during the oxidation process is known as oxidized substance. Hence we can say that an element or compound which have tendency to lose as much electrons to make it stable is its oxidation number now from the given elements boron, carbon and oxygen have 5, 6 and 8 electrons in their shell respectively so they don’t have +7 oxidation state but manganese have 25 electrons in it and there are 7 electrons in its 3d subshell so it can attain +7 oxidation state.
Hence option A is the correct answer.
Note: The increase in oxidation state of an atom, through a chemical reaction, is known as an oxidation; a decrease in oxidation state is known as a reduction. Such reactions involve the formal transfer of electrons: a net gain in electrons being a reduction, and a net loss of electrons being an oxidation. For pure elements, the oxidation state is zero.