One of the free-response questions on the AP* Chemistry exam is a reactions question with eight reactions, such as the example sets.  Of the eight, you are to chose any five that you wish to include as the final answer.  If more than five answers are included in the final answer, only the first five will be graded.  Unless a reaction says otherwise, it can be assumed that all solution are in water, that is, aqueous.  Final answers should be in the form of a net ionic equation, meaning compounds that are soluble in aqueous solution should be written as the ions into which they dissociate, or ionize.  Ions or molecules that do not change in the reaction (e.g. spectator ions) should be omitted.  The reactions do not need to be balanced.

On the example sets provided, it would probably be best to attempt all eight of the questions for the purpose of practicing to write these type of reactions.  It is much nicer come exam time to know all eight and have to choose which ones to leave out than to only know three and not have a clue on two more that you need.  When choosing the five that you want to include in your final answer, try to pick the reactions that you believe are the most correct or accurate.  Remember that there are point deductions for incorrect charges, failure to write soluble compounds as their respective ions, and failure to omit ions or molecules that are unchanged.

To review more about the reactions question before practicing to write these reactions, see reactions questions notes.

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