Chemistry Mid-Year Flashcards
How do you calculate the mean or average rate of reaction ( pyramid 3 way calulation )
Reactant used or product formed
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Rate of reaction | Time taken
How does a successful chemical particle reaction occur.
When the particles collide facing the right way and also have enough speed (energy)
What is the minimum amount of energy that a particle must have to react
Activation energy
What 4 factors make a faster reaction
Higher Temperature
Higher Concentration
Larger Surface Area
Using a Catalyst
How do different factors affect the Collision Theory.
Higher Temperatures mean that the particles have more kinetic energy and collide more
Higher Concentrations mean that there are more particles in the reaction and increases the chance of a succesful reaction
Larger Surface area means that there are more availible particles for reaction
Catalyst lowers the activation energy needed and means that the particles can react quicker
How does temperature effect a reaction
The particles gain more kinetic energy as they get warmer meaning that they become faster and have a higher chance of a succesful reaction.
How do you know if a reaction is happening quicker on a graph
The line is steeper
How do increase the surface area of a solid
Crush them down into smaller piece (powder)
In terms of colission theory, how does surface area effect it
When the surface area is increased, meaning there are more but smaller particles - it means that are more particles availible to react meaning there is a higher chance of successful collisions
How do you know when to draw a tangent
When the question asks for the average over a certain amount of time, it does not want a tangent
When the question asks the the rate of reaction at a certain time, it DOES want a tangent
How does the concentration effect the rate of reaction
When there is a higher concentration it means there are more particles in the reaction and therefore results in the chance for there to be a successful reaction is increased and the rate of reaction becomes faster.
What is a dependent variable
it depends on an independent variable. Dependent variables depend, by some law or rule (e.g., by a mathematical function), on the values of other variables.
What is an independant variable
a variable that stands alone and isn’t changed by the other variables you are trying to measure
What is a control variable
an experimental condition that is kept the same through the experiment, and it is not of any concern in the experiment, niether will it change the outcome of the experiment
