27. For the reaction 2 H2 + O2 → 2 H20, how
many moles of H2O would you get from 2.0169
H2?
a. 2.016 mol H2O b. 1 mol H2O
c. 2 mol H2O
d. 4 mol H2O

2H₂ + O₂ → 2H₂O

You will need to use stoichiometry to solve this problem.  The stoichiometric factor will need to relate H₂ and H₂O.  From the equation, we see that for every two H₂ molecules that react, two H₂O molecules are produced, so the factor is .  The twos reduce, making this a one-to-one ratio.

a. 2.016 mol H₂O

Hint: Because of significant figures, the other three answers would be wrong by default.

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 !

c. orbital shape i hope this is correct