Naturally occurring copper (Cu) consists of two isotopes Cu-63 and Cu-65. Copper-63 has an abundance of 69.09% at 62.930 AMU. Find the percent abundance and AMU for Copper-65. The percent abundance for Cu-65 is
and the mass is
amu. (Type in the correct numbers using 4 significant figures,
using no spaces or units.)
MAKE SURE TO PUT NUMERICAL ANSWERS ONLY
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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 !

wher is the rest of the question