Tip 3: Crystallize and recuperate the alum
In a medium-sized beaker, make a 50/50 mixture of ice and water. Ice will be offered by your TA.
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Place your beaker into the ice water bath. Cool the solution till the temperature of the liquid in your beaker is below 10°C.
Measure the temperature of the solution via the thermometer gave in your lab drawer.
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Make a 10 mL solution containing a 50/50 mixture of ethanol and also distilled water in a 50 mL beaker. Aobtain, use a clean graduated cylinder to measure both liquids. Cool this mixture in your ice bath.
After it has actually cooled for a few minutes, use little parts (5 mL) of this ethanol/water mixture to rinse the inside of the beaker. Some crystals are more than likely stuck to the sides and bottom of the beaker. Rinsing the beaker will assist you to remove them. Simply include a tiny ethanol/water rinse solution to the beaker, swirl, and pour this solution right into the funnel. The ethanol/water mixture likewise serves to wash the isolated crystals as they dry.
After you are done rinsing, keep the crystals in the Buchner funnel via the vacuum attached and on to enable air to circulation via the filter for 10 minutes. This will help to dry your crystals and remove excess water.
Weigh a clean, dry watch glass on the pan balance. Record this worth to the nearemainder hundredth of a gram in your laboratory notebook.
Turn off the vacuum.
Using a clean, dry spatula, rerelocate the alum crystals from the Buchner funnel and onto the watch glass explained above. Weigh the crystals and also watch glass. Record this worth to the nearemainder hundredth of a gram in your laboratory notebook.