Chemistry 🧪⚗️🚐 Flashcards
(22 cards)
What is the definition of reaction rate?
The speed at which reactants are converted into products in a chemical reaction.
True or False: Increasing temperature generally increases the reaction rate.
True
Fill in the blank: The _________ of a solid reactant affects the rate of reaction by increasing the surface area available for collisions.
surface area
What role does a catalyst play in a chemical reaction?
A catalyst increases the reaction rate by lowering the activation energy
How does concentration affect reaction rates?
Higher concentration of reactants usually leads to an increased reaction rate.
What is the effect of decreasing surface area on the rate of reaction?
Decreasing surface area means there are less particles exposed to react so the reaction will take longer
What is the typical effect of increasing temperature on kinetic energy of molecules?
Increasing temperature increases the kinetic energy of molecules.
Define ‘activation energy’.
The minimum energy required for a reaction to occur.
What happens to the reaction rate when a catalyst is added?
The reaction rate increases.
Fill in the blank: The rate of a reaction is often measured in terms of change in _________ over time.
concentration
Which of the following factors is a physical factor affecting reaction rate? (A) Temperature (B) Catalyst (C) Color
A) Temperature
What is the relationship between reaction rate and temperature?
Reaction rate increases exponentially with an increase in temperature.
Name one method to increase the surface area of a solid reactant.
Grinding the solid into a powder.
Fill in the blank: The _________ of a reaction is affected by the physical state of the reactants.
rate
What happens to the reaction rate if the temperature is lowered?
The reaction rate typically decreases.
True or False: All reactions require a catalyst to occur.
False
What is the effect of increasing the surface area exposed on the rate of reaction?
Increasing surface area generally increases the reaction rate.
What does a higher concentration of reactants imply for the frequency of collisions?
It implies a higher frequency of collisions between reactant molecules.
Name one way to decrease the rate of a reaction.
Lowering the temperature or decreasing surface area exposed
Fill in the blank: A reaction with a high activation energy will have a _________ rate at lower temperatures.
slow
True or False: Increasing pressure can affect the reaction rate of gaseous reactants.
True
What does increasing tempreture do to a reaction?
The higher tempreture gives particles more kinetic energy which increases the chance of a succesful and more forceful collison
