Polonium-214 has a half-life of 164 seconds. How much of a 10.0 gram sample would be left after 820 seconds?

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 !

the answer is d. 74.02

it should have an internal chamber and two thermometers sticking out of the top. the internal chamber will also be closed off from the outside.