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Solutions & Solubility. 6.5 Solution Preparation. Solution Preparation from a solid. Standard Solution = a solution for which the precise concentration is known Used in research laboratories and industrial processes Used in chemical analysis and precise control of chemical reactions.
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Solutions & Solubility 6.5 Solution Preparation
Solution Preparation from a solid • Standard Solution = a solution for which the precise concentration is known • Used in research laboratories and industrial processes • Used in chemical analysis and precise control of chemical reactions
Solution Preparation • Equipment needed to prepare a standard solution: • Electronic balance • Volumetric flask
Example • For an acid-base titration, you need to prepare 250 mL of a 0.50 mol/L sodium hydroxide solution
Step 1 • Calculate the number of moles of solute needed.
Step 2 • Calculate the mass of solute needed.
Step 3: The Experimental Procedure Preparing a solution from a solid
Experimental Procedure • Weigh out the required mass of sodium hydroxide in a clean beaker. • Dissolve the solid in 40 – 50 mL of distilled water • Rinse the beaker 2-3 times with small amounts of distilled water and transfer into the volumetric flask • Add distilled water to the flask until the volume is 250 mL • Stopper the flask and mix the contents thoroughly by repeatedly inverting the flask.
Homework • Read pg. 300 – 302 • Do #1, 2, 4a, 5a on pg. 302