Chemical equilibrium occurs when the rates of the reactions a. increase from reactant to product. b. increase from product to reactant. c. decrease from reactant to product. d. equal out in both directions.

Choose all the answers that apply. fluorine (f) has an atomic number of 9 and an atomic weight of 18.99. fluorine has a. 9 protons b. 10 neutrons c. 18 electrons d. an atomic mass of 19 e. at least one isotope