Question

For a reaction A ® B, Ea = 10 kJ mol–1 ,DH = 5 kJ mol–1 . Thus, potential energy profile for this reaction is :

• A.
• B.
• C.
• D.

Answer 1

Answer: (B)

Answer 2

For reaction$\text{A }\overset{\quad\quad}{\rightarrow}\text{ B.}$

$E_{a}\text{ = 10 kJ/mole} ,\Delta\text{H = 5 kJ/moleRxn endothermic because}\Delta\text{H }( + )\Delta\text{H = }\text{E}_{a}\text{ - }\text{E}_{b}$

$\text{5 = 10 - }\text{E}_{b}$

$E_{\text{ab}}\text{ = 10 - 5 = 5 kJ/mole.}$ Then [B].