Cho hợp chất XY₂ tạo bởi 2 nguyên tố X, Y,Z, có hai đồng vị: ⁷⁹Y chiếm 55% số nguyên tử Y và đồng vị ⁸¹Y. Trong XY₂ phần trăm khối lượng của X là bằng 28,51% Tính nguyên tử khối trung bình của X, Y

you need to give more information

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 correct answer is:

a. formation of precipitation

answer: mole of the gas

answer: mole of the gasexplanation: