8. (WCSP24.[x]) Heavy metals, such as calcium, can be extrac…
8. (WCSP24.) Heavy metals, such as calcium, can be extracted from water by a precipitation reaction. Hard water has a Ca2+ ion concentration around 4.24 x 10-3 M. When hard water is mixed with a solution of soda ash (sodium carbonate, Na2CO3), the calcium ions react to form a precipitate and the water is now “softened.” The precipitate can be removed by filtration. a. (8 points) Write the complete balanced equation and the net ionic equation that occurs when Ca2+ and sodium carbonate react. Circle the precipitate. b. (6 points) A 1000 mL soda ash solution was prepared with 5.0 g of sodium carbonate (MW = 106 g/mol). Calculate the concentration (in M) of the sodium carbonate in the solution. Calculate the concentration of sodium ions Enter the concentration of sodium ions below.