For this experiment, we had to test a hygroscopic ionic compound to determine its water of hydration. Basically, we had to calculate how many water molecules were on an ionic compound (ours was FeSO₄ which is Iron (II) Sulfate). To calculate the number of water molecules on the ionic compound, we first had to measure out one gram of the compound. We also had to measure the crucible and lid to it that we put the compound in whilst we burned it. The crucible and lid together measured 20. 40 grams and the ionic compound measured 1 gram. Therefore, putting it together, the crucible, cover, and compound all together measured 21. 40 grams. After we figured out the mass of everything, we put it on a burner and dehydrated it three times- the first one taking 10 minutes on a burner (in a crucible) and the other two times five minutes on the burner (also in a crucible). After we put the substance on the burner, we weighed it. Each time after we put it on the burner came with the exact same number: 21.16 grams. After we found the mass of the crucible, cover, and hydrated sample, and the mass of the crucible, cover, and dehydrated sample, we subtracted the two values to get the mass of water evolved: 0.24 grams. Then, we subtracted that value to the mass of the hydrated sample to get the mass of the dehydrated sample: 0.76 grams. …show more content…
We used the mole conversion formula and calculated that we had 0.013 moles of water. After that we used the same formula to calculate the number of moles of our hydrate which was 0.005 moles. We then divided the number of both moles with the smallest number of moles of what we found. Therefore, we did 0.005/0.005 and 0.013/0.005 and we got the answer one and three respectively. So, the number of molecules in our hydrate was