My project is in the file attached, lots of thanks to Maxineishere for helping me with the essay. You may need adobe reader for this as the files are PDF files, I hope you are satisfied! :)
The answer is descent with modification. Descent with modification practically means that a species have changed appearance wise over long periods of time to adapt to their environments better.
On the prodcuts side (right) Chlorine and Hydrogen already had 2 coefficents to start with. So you needed to change your reactant Chlorine and Hydrogren to two also.
