C6 Ai Flashcards
(54 cards)
What is the rate of a reaction?
The speed of a reaction.
How can graphs represent the rate of a reaction?
Graphs can show how the rate (speed) of a reaction changes.
What does a steeper line on a graph indicate about the rate of reaction?
The faster the rate of reaction.
What happens to the line on a graph over time as reactants are used up?
The line becomes less steep.
What can cause changes in the rate of reaction?
Changes in conditions.
Fill in the blank: The minimum amount of energy needed for particles to react is called _______.
activation energy.
What is collision theory?
An idea that explains reaction rates based on particle collisions.
How does increasing the temperature affect the rate of reaction?
Particles move faster and collide more often.
What is meant by ‘collision frequency’?
How often particles collide.
What happens to the rate of reaction if the reactant particles collide with enough energy twice as often?
The reaction will happen twice as fast.
What is the effect of increasing concentration on the rate of reaction?
More particles result in more collisions.
True or False: All reactions produce the same amount of product regardless of the time taken.
True.
What does a flat line on a reaction graph represent?
No reactants are left.
What is the relationship between the size of reactant pieces and the rate of reaction?
Smaller pieces have a larger surface area, leading to faster reactions.
What is the effect of temperature on the rate of reaction?
Increasing temperature speeds up particle movement, leading to more frequent collisions.
Higher temperatures typically result in faster reactions due to increased kinetic energy of particles.
What factors affect the rate of reaction?
The four main factors are:
* Temperature
* Concentration of a solution (or pressure of a gas)
* Surface area of a solid
* Use of a catalyst
Each factor influences how often particles collide and the energy involved in those collisions.
How does increasing the concentration of a solution affect the rate of reaction?
Higher concentration increases the number of particles in a given volume, leading to more frequent collisions.
This results in a faster reaction rate.
What is the significance of surface area in chemical reactions?
Breaking a solid reactant into smaller pieces increases its surface area, allowing more collisions with other reactants.
A larger surface area to volume ratio enhances the reaction rate.
What is a catalyst?
A catalyst is a substance that speeds up a reaction without being consumed in the process.
Catalysts provide an alternative pathway with lower activation energy.
What is the role of enzymes in chemical reactions?
Enzymes are biological catalysts that facilitate reactions in living organisms.
They are specific to certain reactions and are not consumed in the reaction.
Define ‘collision frequency’.
Collision frequency refers to how often particles collide with sufficient energy to react.
Higher collision frequency typically leads to a faster reaction rate.
Fill in the blank: A catalyst provides a different pathway for a reaction with lower _______.
activation energy.
This allows the reaction to occur more easily and quickly.
True or False: The rate of reaction will double if the collision frequency doubles.
True.
Doubling the collision frequency implies more reactions occur in the same time frame.
What happens when magnesium ribbon is powdered for a reaction with hydrochloric acid?
The powdered magnesium will react faster than the ribbon due to increased surface area.
This allows for more frequent collisions with acid particles.
