Which of the following elements are already balanced in this equation? FeS₂ + Cl₂ → FeCl₃ + S₂ Cl₂

Fe and S are already balanced in this equation

Balanced indicates that the number of elements in question has the same number of atoms both on the left side (the number on the reactants side) and on the right side (the number on the product side)

Even though one of the elements is said to be balanced, the chemical equation as a whole cannot be said to be balanced, because the chemical equation has several components of the constituent elements.

To balance chemical equations, a coefficient in front of the compound is usually added either in the reactants or products

Reaction

FeS₂ + Cl₂ → FeCl₃ + S₂Cl₂

From this equation, it can be shown that: the Fe and S elements are balanced because the numbers are equal both on the left and right, while the Cl elements are not yet balanced

Fe, left=1, right=1 ⇒ balanced

S, left=2, right=1 ⇒ balanced

Cl, left=2, right=5⇒ not balanced

For balanced equations:

2FeS₂ + 5Cl₂ → 2FeCl₃ + 2S₂Cl₂

why do the isotopes of a particular element behave differently in nuclear reactions but the same in chemical reactions? chemical reactions involve changes to electrons in an atom; isotopes do not differ in electrons, and so they react the same way during chemical changes.

the millers tale is the answer.