1. HW 11-2 Exploring Ea and temperature
Link to activation energy hydrogen chlorine cannon
1A) NO reaction initially observed when hydrogen and chlorine mixed. Why?
COLLISIONS BETWEEN H2 AND Cl2 MOLECULES DON’T HAVE ENOUGH ENERGY TO OVERCOME ACTIVATION BARRIER

2. Burning mg to initiate reaction
Link to activation energy hydrogen chlorine cannon
1C) How does light initiate the reaction?
ANS: High energy UV light breaks bonds between Cl atoms to produce highly reactive Cl atoms with unfilled energy levels.
Propane combustion ignited by sparkler

3. HW 11-2 # 3a and 3b
Glow tube T
3A and 3B) Glow same at same T. Glow sticks are brighter at higher temperature; do not glow as brightly at lower T

4. HW 11-2, #4 pHET Simulation questions
Link to Phet Simulation
4A) COLLISIONS DO NOT HAVE SUFFICIENT ENERGY TO OVERCOME ACTIVATION ENERGY, EA.
4B) ADDING HEAT ENERGY INCREASES THE KINETIC ENERGY (ENERGY OF MOTION) OF THE MOLECULES
4C) NO ALL MOLECULES DO NOT HAVE THE EXACT SAME ENERGY SINCE THERE ARE NOT ALL MOVING AT THE EXACT SAME SPEED.
4D) AS T INCREASES, ENERGY OF COLLISIONS INCREASES. THE NUMBER OF MOLECULES WITH ENERGY ABOVE THE ACTIVATION ENERGY INCREASES.
4E) CHANGING TEMPERATURE PRIMARILY CHANGES THE ENERGY OF THE COLLISIONS

5. Higher % made at when jumpers have greater E1
1/5 x100 = 20% 3
3/5 x100 = 60%

6. Hw 11-2, #6 impact of Temp Link to collision theory animation 1
RUN 12-4 ON ANIMATION

7. Hw 11-2, #6
At 100 K no molecules are colliding with E ≥ Ea; A higher % have E ≥ Ea as T increases.

8. Impact of temperature on Reaction Rate
As the temperature of a reaction increases, the % of molecules with Energy ≥ Ea (the activation energy INCREASES

9. Hw 11-2, 19a AND 19b
Activation energy of NO + CS2
Jimmy Kimmel NO + CS2
19A) NO and CS2 Molecules are not colliding with enough energy to overcome the activation barrier
19B) Spark provides enough energy so that NO and CS2 molecules are now colliding with enough energy to overcome the activation barrier.
Can Steam Light a Match?
Light match steam

10. Summary OF Collision Theory In order to react molecules must:
COLLIDE
In the correct ORIENTATION
With sufficient ENERGY

11. Rxn requires: a hard collision in the right spot!

12. Hw 11-2
21) Mg reacts fastest with 6M HCl; higher concentration increases # of collisions.
22) 6M HCl reacts fastest Zinc powder; greater surface area increases # of collisions.
23) O2 and N2 gases react fastest at 500 oC due to higher energy of collisions.