Someone help me plz

Question

Hydrochloric acid can dissolve solid iron according to the following reaction.

Fe(s)+2HCl(aq)→FeCl2(aq)+H2(g)

Part A-

What minimum mass of HCI in grams would you need to dissolve a 2.1 g iron bar on a padlock?  

Part B-

How many H2 would be produced by the compete reaction of the iron bar?

Answer 1

Part A:

So the first step here is to convert the mass of iron to moles.

2.1g Fe x 1 mol /55.85g = .038 moles Fe

Now the ratio from the equation to find the moles needed of HCl:

.0376 mol Fe x 2 mol HCL/1mol Fe = .0752 mol of HCl required {I will round at the end of the problem}

Now convert that quantity of HCl into mass:

.0752 mol HCl x 36.45g / 1 mol HCl = 2.7g of HCl needed.

Part B:

To calculate how much H₂ it would produce, start with the limiting reactant, which was the quantity of iron, and multiply by the ratio from the balanced equation.

.0376 mol Fe x 1 mol H₂ /1 mol Fe = .0376 mol H₂

Now convert that to mass: .0376mol H₂ x 2.02g H₂/1 mol H₂ = .076g of H₂ would be produced.