Question

Oxidation states are important for keeping track of electrons in oxidation-reduction reactions. Here are some general rules to remember: In most cases, oxygen has an oxidation state of ?2. Group 1 and group 2 elements on the periodic table have +1 and +2 oxidation states, respectively. In most cases, hydrogen has an oxidation state of +1. Many elements can have more than one oxidation state. In such cases, use the other elements in the compound whose oxidation states are known to determine the oxidation state of the element that varies.

Neutral compounds In a neutral compound, the sum of the oxidation states is zero. Note that the sign of the oxidation states and the number of atoms associated with each oxidation state must be considered. In H2O, for example, each hydrogen atom has an oxidation state of +1 and each oxygen atom has an oxidation state of ?2 for a total of 2(+1)+(?2)=0. Part A What is the oxidation state of an individual carbon atom in CaCO3? Express the oxidation state numerically (e.g., +1). SubmitHintsMy AnswersGive UpReview Part Part B What is the oxidation state of an individual nitrogen atom in HNO3? Express the oxidation state numerically (e.g., +1). SubmitHintsMy AnswersGive UpReview Part Ions In an ion, the sum of the oxidation states is equal to the overall ionic charge. Note that the sign of the oxidation states and the number of atoms associated with each oxidation state must be considered. In OH?, for example, the oxygen atom has an oxidation state of ?2 and the hydrogen atom has an oxidation state of +1, for a total of (?2)+(+1)=?1. Part C What is the oxidation state of an individual sulfur atom in SO32?? Express the oxidation state numerically (e.g., +1). SubmitHintsMy AnswersGive UpReview Part Part D What is the oxidation state of each individual carbon atom in C2O42?? Express the oxidation state numerically (e.g., +1).