Which of the following statements about compounds is false?
a. compounds include two types: ionic and covalent.
b. the properties of compounds are different than the elements that make them up.
c. compounds are two or more types of atoms bonded together.
d. compounds can be separated by physical methods.?

neutrons are in the middle of the atom and the electrons, which are much smaller.

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 !