b. Give reasons. Because it is possible to remove the water of hydration by heating the hydrate. 3. A student heated an unknown hydrate, Na2SO4·XH2O, in a crucible. The water was driven off, leaving the anhydrous salt in the crucible. After cooling, the mass of the anhydrous salt and water lost was calculated. The mass of the anhydrous salt was 0.695 g and the mass of water lost was 0.895 g. a. Calculate the moles of anhydrous salt in the sample. Show all steps. (The molar mass of this salt is 142.04 g.) mol anhydrous = 0.695 g / 142.04 g = 0.00489 mol
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