Question

For each of the following examples that affects the rate of a reaction, state which of the two options will speed up the reaction and explain why & what happens at the molecular level and collision theory to cause it to speed up? *THIS IS A THREE-PART QUESTION* Please explain all the steps you make and why you chose a specific answer.

Answer 1

4a. Cool down your drink faster

In this case, what happens is that the temperature of the hot drink will come into equilibrium with the ice until the ice melts and they both reach an equilibrium temperature. The speed with which this happens will depend on the area of contact between the ice and the drink. Now, if we want it to be faster, we must increase the contact area, that is, we must add crushed ice since there will be more contact between the ice and the drink. At the molecular level, what happens is that the molecules that move freely in the hot drink will gradually slow down due to the decrease in temperature.

4b. Reaction Fe3O4+4H2 --->3Fe+4H2O

We have to identify first if this is an endothermic or exothermic reaction. I

If the reaction is exothermic, an increase in temperature will displace the reaction to the reactants. If the reaction is endothermic, an increase in temperature will shift the equilibrium to the products.

It is an endothermic reaction, since the reaction energy is 149.8kJ/mol. Therefore, if we want to increase the rate of the reaction (reaction occurs faster) we have to lower the temperature.

4c.Reaction 6H2O(l) + 6CO2 --->C6H12O6+6O2

In a reaction, if we want to increase the rate we must increase the concentration of the reactants. So, we have to increase the concentration of CO2 to make this reaction occurs faster.