Hydrogen gas reacts with oxygen gas to form water. At STP, how many liters of hydrogen gas react with 32.4 liter of oxygen gas? (H2 + O2 -> H2O)

I think its 1.2L? i may be wrong

Explanation:

Recall old Avogadro's hypothesis

Equal volumes of gases contain AN EQUAL NUMBER of PARTICLES

And thus if there are

2.4

⋅

L

of dihydrogen, stoichiometric equivalence requires

1.2

⋅

L

of dioxygen. How many litres of water g

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 !