Qrtr 4 final

C​ 6​
H​ 6​
+ Br​ 2​ ​
​→​ ​ C​ 6​
H​ 5​
Br + HBr
5 Which of the following changes will cause an increase in the rate of the above reaction?
A increasing the concentration of Br​ 2
B decreasing the concentration of C​ 6​
H​ 6
C increasing the concentration of HBr
D decreasing the temperature
Increasing the concentration of a reactant will work sort of similarly to increasing the heat. As a
result of the higher concentration of reactants (ie a higher concentration of particles), more particles
will collide which will speed up the reaction.
2CO + O​ 2​
→ 2CO​ 2
6 If the above reaction takes place inside a sealed reaction chamber, then which of these procedures
will cause a decrease in the rate of reaction?
A raising the temperature of the reaction chamber
B ​increasing the volume inside the reaction chamber
C removing the CO​ 2​
as it is formed
D adding more CO to the reaction chamber
Increasing the volume of the container will decrease the rate of the reaction. As I talked about
concentration before, it has a lot of influence on the rate of a reaction. In a closed container, the
concentration changes depending on the volume of said container. If you took a 100 g sample of a
reaction and put it in a 1 liter container, the reaction will proceed at a quicker rate than if the same
reaction happened in a gallon container. This comes back to the movement and collision of the
particles (just like everything does for these notes). The particles in the 1 liter container will bounce off
the walls of the container more often and therefore collide with other particles of the reaction more
often. There’s less space for everything to happen, so the particles keep “bumping” into each other. In
the 1 gallon container, this will also happen, but at a slower rate. So to decrease the rate of the
reaction, increase the volume of the reaction chamber.
7 A catalyst can speed up the rate of a given chemical reaction by
A increasing the equilibrium constant in favor of products.
B lowering the activation energy required for the reaction to occur.
C raising the temperature at which the reaction occurs.
D increasing the pressure of reactants, thus favoring products.
A reaction needs a specific amount of energy to proceed. This is called the activation energy.
Once the particles in a reactant reach or receive this energy, they can proceed with the reaction and
convert into the product. This dictates the rate of the reaction- when the particles reach this energy.
This can be hastened or delayed using many things like temperature and concentration, and of
course, catalysts. Catalysts speed up reaction by lowering the activation energy a reactant needs to