During a lab, you heat 1.04 g of a NiSO4 hydrate over a Bunsen burner. After heating, the final mass of the dehydrated compound is 0.61 g. Determine the formula of the hydrate and also give the full name of the hydrate.

Question

jfraser · Answer

the hydrate contains both the salt, NiSO4, and water. Heating the hydrate removes the water, but leaves behind the dehydrated salt.

Find the moles of salt leftover, using the molar mass of NiSO4.

Find the moles of water that were evaporated away, using the molar mass of water.

Find the mole ratio, water/salt. That will be a whole #, or at least really close to a whole #. The formula of the hydrate will be$$NiSO_{4}*nH_{2}O$$ where "n" is the ratio you just solved for. The name of the hydrate will be the name of the salt with its hydrate # as a prefix. For example, CuSO4*5H2O is copper (II) sulfate pentahydrate