Use the chemical equation below to complete the activity.
A student makes the following statements:
Statement 1) Hydrogen always has the same oxidation number, so it has an oxidation number of +1 in both the reactant H2 and product HBr.
Statement 2) Bromine is in Group VIIA, so it has an oxidation number of –1 in both the reactant Br2 and product HBr.
Statement 3) Neither hydrogen nor bromine changes oxidation states, so the reaction is not a redox reaction.
Evaluate each statement for accuracy and describe the mistakes that the student made, then you determine whether or not the reaction is a redox reaction. Explain your answer; if redox then why and if not redox, then why not.
Statement 1 is accurate. Hydrogen always has an oxidation number of +1.
Statement 2 is accurate. Bromine is in Group VIIA and has an oxidation number of -1.
Statement 3 is incorrect. The reaction is a redox reaction because the oxidation number of bromine changes from -1 in the reactant Br2 to +1 in the product HBr.
The reaction is a redox reaction because the oxidation numbers of the reactants and products are different. The oxidation number of bromine changes from -1 in the reactant Br2 to +1 in the product HBr, and the oxidation number of hydrogen remains the same at +1.