Iron(111) chloride, fec13 , can be made by the reaction of iron with chlorine gas. how much iron, in grams, will be needed to completely react with 58.0 g of c12

The balanced chemical equation that describes this reaction is:
2Fe + 3Cl2 > 2FeCl3

Using the periodic table:
molar mass of iron III = 55.845 grams
molar mass of chlorine = 2*35.453 = 70.906 grams

From the balanced equation above, 2 moles of iron are required to react with 3 moles of chlorine.
This means that:
2*55.845 = 111.69 grams with iron are required to react with 3*70.906  = 212.718 grams of chlorine.
To know the amount of iron needed to react with 58 grams of chlorine, we will simply use cross multiplication as follows:
mass of iron = (58*111.69) / (212.718) = 30.45355 grams

A catalyst speeds up a reaction by lowering the activation energy.

Explanation:

A catalyst has no effect on the equilibrium of a reaction.A catalyst does not add energy to a reaction neither does a catalyst consumed in a chemical reaction .

Therefore, A catalyst speeds up a reaction by lowering the activation energy.