What volume will 0.875 moles of kr occupy at stp?

               Volume =  19.6 L

                     As we know that one mole of any Ideal gas at standard temperature and pressure occupies exactly 22.4 dm³ volume.

Using this reference, we can calculate the volume occupied by Krypton (Ideal situation) as,

                     1 mole of Kr occupies  =  22.4 L of Volume

So,

                  0.875 moles of Kr will occupy  = X L of Volume

Solving for X,

                       X =  (0.875 mol × 22.4 L) ÷ 1 mol

                      X =  19.6 L

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !