Well Known Science Knowloage Flashcards
What is independent variable?
What you change
Whats the dependant variable?
What you measure
What is a control variable?
What you keep the same
Explain how there can be different units for measuring
rate of reaction.
The units chosen depend on what aspects of the reaction are being observed and the experimental conditions.
List some factors that can affect the rate of a chemical
reaction.
include temperature, concentration of reactants, surface area.
Explain using collision theory how temperature,
concentration/pressure, surface area and catalyst affect
the rate of a reaction.
Temperature boosts energy, concentration increases collisions, surface area facilitates contact, and catalysts lower activation energy, all impacting reaction rates via collision theory.
Describe how temperature affects the rate of reaction.
When it’s hotter, the molecules move faster, bump into each other more, and make reactions happen faster.
Describe how surface area of a solid can be increased.
Breaking a solid into smaller pieces or turning it into a powder increases its surface area, facilitating more interactions in chemical reactions.
Describe how changing the surface area changes the rate
of reaction.
Smashing or cutting a solid into smaller bits makes things happen faster in a reaction because there are more chances for things to coliding into each other.
Calculate the surface area to volume ratio.
To calculate the surface area to volume ratio, divide the surface area by the volume of the object or substance in question.
Describe how changing concentration affects the rate of
reaction.
increases the number of successful collisions and the reaction rate.
Use collision theory to explain how changing the
concentration alters the rate of reaction.
Increasing the concentration of reactants means there are more particles in the same space, leading to more frequent collisions and a higher likelihood of successful reactions
Describe how changing pressure of gaseous reactants
affects the rate of reaction.
Higher pressure squeezes gas particles together, making them collide more often and speeding up the reaction.
Describe what the activation energy of a reaction is.
Activation energy is the minimum amount of energy required for a chemical reaction to occur. It represents the energy barrier that reactant molecules must overcome to transform into products.
State what is a catalyst
A catalyst is a substance that speeds up a chemical reaction by providing an alternative reaction pathway with a lower activation energy, without being consumed in the process.
