How many grams of Mg must react with HCl in order to produce 40.0 ml of hydrogen gas at 22 degrees celsius and 1.02 bar?

Question

If the magnesium ribbon weighs 1.83mg/mm, how many mm of the ribbon will you require?

Thanks in advance for your help!!

Answer 1

Mg + 2HCl ==> H2 + MgCl2
Use PV = nRT and solve for n = mols H2 gas at the conditions of the problem.

Use the coefficients in the balanced equation to convert mols H2 to mols Mg.

Then g Mg = mols Mg x atomic mass Mg (in grams). Convert to mg.
Finally, length of Mg is
1.83 mg/mm x ?mm = mg Mg from the last step. Solve for ?mm.