A compound of iron and oxygen is a ferrous oxide and it is totally different from the mixture if iron and oxygen. Compounds are made up of elements that are chemically combined together.A compound of iron and oxygen has a different property from the original atoms that forms it. To form the compound, iron and oxygen is chemically combined by the loss and gain of their valence electrons. The mixture of oxygen and iron contains individual substances that still retains their original composition. Mixtures are not chemically combined. The mixture is made up of oxygen gas and iron which are different states of matter.
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it is a good conductor
1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄
2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%