Final answer:
Approximately 0.092% of a 5.02 g sample of MgNH4PO4·6H2O would be lost when washed with 20 ml of water, given the solubility of 0.023 g per 100 ml of water.
Step-by-step explanation:
The student's question is asking what fraction of MgNH4PO4·6H2O would be lost when a 5.02 g sample is washed with 20 ml of water, given that the solubility of the compound is 0.023 g/100 ml. To calculate the fraction lost, we need to first determine how much of the compound will dissolve in 20 ml of water.
The solubility given is for 100 ml, so for 20 ml it would be:
(0.023 g/100 ml) × 20 ml = 0.0046 g
So, 0.0046 g of MgNH4PO4·6H2O will dissolve in the 20 ml of water used for washing. Next, we calculate the fraction of the original sample this represents:
Fraction lost = Amount dissolved / Original amount = 0.0046 g/5.02 g = 0.00091633...
Therefore, approximately 0.00092 (or ~0.092%) of the original MgNH4PO4·6H2O sample would be lost during the washing process.