In order to find the number of moles with a given mass of Helium, we need to use its molar mass, which is 4.0026g/mol, therefore we will have:
4.0026g = 1 mol of Helium
91.5g = x moles of Helium
x = 22.86 moles of Helium in 91.5 grams
Because some atoms<span> are more stable when they </span>gain or lose<span> an </span>electron<span> and </span>form ions<span>.</span>
a. mass of iron = 69.92 g
b. percent yield = 93%
<h3>Further eplanation
</h3>
Percent yield is the compare of the amount of product obtained from a reaction with the amount you calculated
General formula:
Percent yield = (Actual yield / theoretical yield )x 100%
An actual yield is the amount of product actually produced by the reaction. A theoretical yield is the amount of product that you calculate from the reaction equation according to the product and reactant coefficients
a.
Reaction
Fe₂O₃+3CO⇒2Fe+3CO₂
MW Fe₂O₃ : 159.69 g/mol
mol Fe₂O₃

mol Fe₂O₃ : mol Fe = 1 : 2
mol Fe :

mass of Fe(Ar=55.845 g/mol) :

b.
actual yield = 65 g
theoretical yield = 69.92 g
percent yield :
