Practical investigations
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I have got to carry out a design experiment of e.g. ethanedioic acid and sodium hydroxide, using a titration. Can you please tell me the method I should use? Could you also tell me how to find the solubility of a substance? HELP! Thanks!!
Igloo says
The solubility of a substance is the maximum quantity of it capable of dissolving in a fixed quantity of a solvent (often water).
To determine the solubility means making up a saturated solution, and then analysing it to determine its concentration. This is its solubility.
In the case of ethanedioic acid, a titration with an alkali (e.g. sodium hydroxide) can be used to measure its concentration.
I suspect that this is some sort of class exercise, so I shall not be giving you a detailed procedure to follow, but here are the stages:
• Make a saturated solution, and leave overnight.
• Separate off the solution from the undissolved solid.
• Titrate portions of this solution with a standard solution of sodium hydroxide, using a suitable indicator.
From your titration readings you can calculate the concentration of the ethanedioic acid, and from this you can convert this to the units of solubility required (usually grams per 100 g of solvent)
Since solubility varies with temperature you need to quote the temperature at which the saturated solution was made up.
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Risk assessment
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updated: 17 January 2006
