Presentation on theme: "SCH3U Solutions and Solubility"— Presentation transcript:
1 SCH3U Solutions and Solubility 8.5 Acid-Base ReactionsSCH3USolutions and Solubility
2 Reactions Involving Acids Acids take part in several characteristic reactions:Active metals react with acids in a single displacement reactionactive metal + acid hydrogen + ionic compoundMg(s) HCl(aq) H2(g) MgCl2(aq)
3 Reactions Involving Acids All acids react with carbonates in a double displacement reactioncarbonate + acid carbon dioxide + water + ionic compoundNa2CO3(s) + 2HNO3(aq) CO2(g) + H2O(l) + 2NaNO3(aq)
5 Reactions Involving Acids Acids react with bases in another double displacement reaction often called a neutralization reactionbase acid ionic compound waterNaOH(aq) + HCl(aq) NaCl(aq) + H2O(l)
6 SCH3U Solutions and Solubility 8.5 Acid-Base TitrationSCH3USolutions and Solubility
7 Acid-Base Titration Titration Titrant a laboratory procedure involving the carefully measured and controlled adding of a solution from a buret into a measured volume of a sample solutionit is used to determine the concentration of substances in solutionTitrantthe solution in the buret during a titration (standard solution with KNOWN concentration)
9 Titration of an Acid with a Base In the buret standard solution of base (KNOWN concentration)In the flask precise volume of acid (UNKNOWN concentration)In the flask indicator to detect the end point
10 Titration of a Base with an Acid In the buret standard solution of acid (KNOWN concentration)In the flask precise volume of base (UNKNOWN concentration)In the flask indicator to detect the end point
11 The EndpointEndpointthe point in a titration at which the indicator changes colourthis is at, or close to, the point at which the titrant and sample in the flask have completely reactedPHTH titration
13 Steps of a Titration Place standard solution in buret Place a precise volume of a solution of unknown concentration in a flaskAdd an indicator to the flaskRecord the volume in the buret as your initial readingOpen the stopcock of the buret and allow the standard solution to enter the flask, while swirling the flaskSlow down the flow of standard solution being added to ensure you don’t surpass the endpoint by too muchOnce the end point is reached, record the final volume in the buretSubtract the initial volume from the final volume in the buret to obtain the total volume of standard solution used to neutralize the unknown solution.
14 A Titration Sample Problem 25.0 mL of an acid rain sample containing sulfurous acid was analyzed in a laboratory using a titration with a standard solution of sodium hydroxide ( mol/L). Use the evidence given in the following table to determine the concentration of the sulfurous acid.