In an experiment, 2.54 grams of copper completely reacts with sulfur, producing 3.18 grams of copper(I) sulfide. What is the total mass of the sulfur consumed?

1 Answer
Mar 13, 2016

#0.64# #g# of sulfur.

Explanation:

Every chemical reaction conserves mass. If you finish with #3.18# #g# #Cu_2S#, and #2.54# #g# of copper metal were used, the balance, the difference between the end mass and the mass of copper MUST be the mass of sulfur that reacted.

So #"mass of sulfur:"# #=# #"Mass of copper sulfide"# #-# #"Mass of copper"# #=# #(3.18-2.54)*g# #=# #0.64*g" sulfur"#.

The point to remember is that mass is conserved in every chemical reaction.