How many grams of IRON are

contained in a 245 gram sample

of Fe2O3?

Explanation:

Hello!

In this case, since we have 245 of iron (III) oxide, we first need to compute the moles contained there:

Now, as 1 mole of iron (III) oxide is related to 2 moles of iron, due to iron's subscript in the molecule, we get the moles of iron itself:

And the mass is computed based on the atomic mass of iron:

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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%

a) the particles of the chair are strongly held together.