7) In the diagram below, the left circle represents gaseous carbon and sulfur before they react; the diagram on the right represents the compound that results when these atoms combine. BEFORE REACTION AFTER REACTION S S S S S A) Take an inventory. Count the particles in each diagram and list them in the table below. Before Reaction After Reaction C atoms CS2 molecules Satoms C atoms B) Which reactant (C or Satoms) is in excess? C) Which reactant (C or Satoms) limits the reaction? . When writing an equation to represent this chemical change, remember, the equation shows how carbon would combine with sulfur no matter how many total atoms you start with, or what is leftover (in excess). Just as you did with the nuts and bolts combination, we want a general statement that tells us how carbon combines with sulfur. . D) Write a chemical equation to represent how carbon atoms react with sulfur atoms. 8) In the chemical equation below: 2Na+S Na2S What is the difference between using 2 as a coefficient (e.g. 2Na) and using it as a subscript (e.g. Na2S)