1) A student recrystallizes 1.00 g of the unknown compound from 50 mL of water. After...

1) A student recrystallizes 1.00 g of the unknown compound from 50 mL of water. After allowing the mixture to cool to room temperature (25 °C), the student collects the recrystallized compound using vacuum filtration. What is the theoretical maximum percent recovery of the unknown compound for this recrystallization step?

2)A student recrystallizes 1.00 g of the unknown compound from 50 mL of water. After allowing the mixture to cool in an ice bath (0 °C), the student collects the recrystallized compound using vacuum filtration. What is the theoretical maximum percent recovery of the unknown for this recrystallization step?

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Expert Solution

Below two reasons for loss of compounds

1) In the filtration step, material was lost on filter paper: this is common at 25 ^o C and 0 ^o C

2) Material did not completely crystallize from solution: The percentage recovery depends on the final temperature of the solution after recrystallization, as at 0 ^o C the solute will most likely be less soluble than at room temperature

% of recovery = (amount pure product recovered/amount crude product used) X100

If you know the solubility of your unknown compound in water then we can calculate the exact % of recovery.

You will get maximum recovery filtration at 0 ^o C than room temperature filtration

queen_honey_blossom answered 1 year ago

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