The model represents a fluorine (F) atom

what is the mass of the atom

19

Explanation:

The mass of an atom is given by its mass number. This is because the mass of an atom is concentrated at the nucleus.

Mass number = number of protons + number of neutrons

Protons and neutrons are the most massive particles in any atom.

Protons are the positively charged particles in an atom

Neutrons are uncharged particles.

  So, the mass number of this atom is:

      Mass number  = 9 + 10 = 19

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 !

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