Calcium sulfate is a white solid found as two hydrates, a hemihydrate known as plaster of Paris and a dehydrate known as gypsum. The hemihydrate is a white solid. Given that the molar mass of the anhydrous calcium sulfate is 136.14 g/mol, the molar mass of the hemihydrate is 145.15 g/mol, and the molar mass of water is 18.015 g/mol, which formula gives the correct ratio for the hemihydrate

2(CaSO4)*H2O

Explanation:

To solve this question we need to find the moles water, H2O, of calcium sulfate, CaSO4 as follows:

The molar mass of the anhydrous CaSO4 are 136.14g/mol and the molar mass of the hemihydrate is 145.15g/mol. The differences in molar mass represents the additional mass that water is producing:

145.15g/mol - 136.14g/mol = 9.01g/mol

A 1 mole of water weighs 18.015g/mol, the additional mass of water is due the addition of 1/2 moles of H2O. That means we have 1 mole of CaSO4 per 1/2 mole of H2O. That is the same:

2(CaSO4)*H2O

And this is the formula that gives the correct ratio for the hemihydrate.

hurricanes form when warm, moist air from the ocean surface quickly rises into the atmosphere and forms storm clouds and rain. when the clouds are formed, heat is released which warms the cool air in the upper regions of the atmosphere so that the cycle can continue. which two phases of the water cycle are repeated in this process?