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Title: Homework help Post by: carloxio on May 27, 2009, 12:35:09 PM i need help with a homework question: write the equation for the reaction of af aqueous solution of sodium chloride and silver acetate what type of reaction is this?
Title: Re: Homework help Post by: kingchemist on May 27, 2009, 03:25:56 PM I think you need to check the solubility of the two reactants and of the two possible products.
Silver acetate and sodium chloride are both soluble as they are present at the start of the reaction as solutions. Soluble ionic compounds like these exist as separate, free ions in a solution eg Ag+(aq), CH3COO-(aq), Na+(aq) and Cl-(aq). The only way a reaction will occur with these if one of the possible products, silver chloride or sodium acetate is insoluble. For example if a solution of lead(II) nitrate is mixied with a solution of sodium iodide, a reaction occurs because one of the products, lead(II) iodide, is insoluble and 'comes out' of the mixture as a precipitate. Pb2+(NO3-)2(aq) + 2Na+I-(aq) ---> Pb2+(I-)2(s) + 2Na+NO3-(aq) This can also be written more correctly as Pb2+(aq) + 2NO3-(aq) + 2Na+(aq) + 2I-(aq) ---> Pb2+(I-)2(s) + 2Na+(aq) + 2NO3-(aq) If spectator ions are eliminated, the essential reaction is - Pb2+(aq) + 2I-(aq) ---> Pb2+(I-)2(s) So as a solid 'comes out' of a solution during a chemical reaction, it is called precipitation. Also the reaction can be described as double decomposition as the reacting salts change 'partners' You will need to consider how this applies to the reaction in the question. Title: Re: Homework help Post by: spock on May 28, 2009, 08:37:49 AM I've also heard this type of reaction referred to as
double replacement or double displacement |