rates of reaction

Question 1

how does concentration affect the rate of reaction

Answer 1

-more particles in a given volume
-results in a higher frequency of successful collisions
-therefore the rate of reaction increases

Question 2

how does the surface area increase the rate of reaction

Answer 2

-increased surface area leads to more surfaces for collisions to take place on
-increases frequency of successful collisions, increasing the rate of reaction

Question 3

how does temperature increase the rate of reaction

Answer 3

-increases the temperature
-particles have greater kinetic energy
-increases the frequency of collisions
-particles also collide with more energy
-frequency of successful increases, the rate of reaction increases

Question 4

why are results of an experiment less accurate when the rate of reaction is higher

Answer 4

-the reaction occurs at a quicker rate, so it is more difficult to stop the timer accurately
-it is harder to correctly judge the end point

Question 5

how can you measure how catalysts affect rate

Answer 5

-decomposition of hydrogen peroxide
-add hydrogen peroxide to a beaker attached to a gas syringe with a bung
-add manganese oxide powder to the hydrogen peroxide
-measure the volume of gas produced at regular time intervals and record the results
-repeat the experiment using copper oxide(same amount of catalyst)
-plot a graph

Question 6

catalyst

Answer 6

Catalyst: A substance that speeds up a chemical reaction while remaining chemically unchanged at the end of
the reaction.

A catalyst is not used up in a reaction.

A catalyst speeds up a reaction by providing an alternative pathway with lower activation energy.