The weight of a china dish with a saturated solution of sodium nitrate at 40°C is 80 g. After evaporating

the whole solution the dish's weight along with the crystals is 40 g and solubility of NaNO3 at 40°C is
20 g. What is the weight of empty china dish ?

2 answers

80 g = dish+xtals+H2O
-40 g = dish+xtals
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40 g = dish+xtals
-20 g = xtals
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20 g = dish
30g