Which of the following is the term used to describe a set of elements whose properties tend to be largely predictable based on position on the periodic table?

Explanation:

Elements which belong to same group show similar chemical properties.

This is because elements that lie in the same group have same number of valence electrons. Hence, they tend to show same type of reactivity which makes them exhibit similar chemical properties.

As chemical properties are defined as the properties which tend to show difference in chemical composition of a substance.

For example, toxicity, reactivity, combustion etc are all chemical properties.

Thus, we can conclude that group is the term used to describe a set of elements whose properties tend to be largely predictable based on position on the periodic table.

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 !