Answer:
- the 2 in this formula is called the subscript. It refers only to the element preceding it. In this case the F (fluorine).
- in some chemical formulas it is necessary to use parentheses. The subscript outside the parentheses refers to all the elements inside the parentheses. In this example there are: one Al (aluminum), three N (nitrogen), and nine O (oxygen).
- the 3 in this formula is called the coefficient. It refers to each element that follows. In this case there would be 3 Ba (barium) and 3 F2 (a total of 6 fluorine).
Explanation:
