Solutions & Solubility 6.5 Solution Preparation. Solution Preparation from a solid Standard...

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Transcript of Solutions & Solubility 6.5 Solution Preparation. Solution Preparation from a solid Standard...

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

Equipment needed to prepare a standard solution: Electronic balance Volumetric flask

Solution Preparation

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