Answer: addition of electrons and hydrogen ions. loss of electrons and addition of hydrogen ions. loss of electrons and either addition or loss of hydrogen ions.
I think the answer is (D)
Line - A: (15/10) = 1.5 inch/second
Line - B: (0/10) = 0
Line - C: (10/10) = 1.0 inch/second
Line - D: (-25/20) = -1.25 inch/second
<em>Line-A</em> represents the greatest speed.
The answer is that the reverse arrows pointing to the left needs to release energy. The molecules in the gas state are free such that they can travel from one point to another easily. They have the highest amount of energy. So, if you want the molecules to come closer together, you need to remove the energy to keep them in place. Therefore, the arrows pointing to the right require removal of energy.
