AP Chemistry 1.1 Chemical Reaction Rates
AP® Chemistry: Reaction Rates Drill 1, Problem 1. Which of the following influences the rate of a chemical reaction?
|AP Chemistry||Chemical Reaction Rates|
First, let's think about what a chemical reaction is. It's when two or more molecules react
with each other to form a different molecule.
Going even more granular, a reaction takes place when collisions take place between the
reactant particles to form a different arrangement of molecules.
Let's look at the first answer choice. Concentration of reactants.
Reactants are just a fancy name for the molecules that are reacting with each other.
The left side of a chemical equation.
Thinking logically, if we add more molecules
to a solution, because there are more molecules and hence more atoms to collide with each
other, the reaction will typically go faster. Yes, more collisions means faster.
So the concentration affects the rate. But before we just pick answer choice A, let's
keep looking. Answer choice B. The temperature. Temperature
is a measure of the average kinetic energy. Kinetic means movement, so in other words,
temperature affects the number of collisions that take place.
Higher temperatures would help speed up a reaction.
Therefore, Choice (B) is also a true statement.
We know that C must be true because the only
choices we have left are C and D...and answer choice D says ALL OF THE ABOVE.
But let's just take a look at C to be extra sure. The presence of a catalyst.
Well of course a catalyst will influence the speed, or rate, of a chemical reaction.
That's the point of a catalyst...to help the reactants form products faster. So again,
the rate is affected. Our answer's D.
As in, "Dogalyst..."