During an exothermic reaction, is heat released or absorbed?
Released
What is the unit used for heat?
Joules (J) or Kilojoules (kJ)
How does increasing temperature affect the rate of a reaction?
It increases the reaction rate by giving particles more kinetic energy, leading to more effective collisions.
What happens to the equilibrium when the concentration of a reactant is increased?
Shifts to the rght/side of the products.
What is the role of a catalyst in a chemical reaction?
To speed up the reaction without being consumed.
Is the melting of ice an endothermic or exothermic process?
Endothermic
What is the definition of temperature?
Temperature measures the average kinetic energy of particles
What must happen for a reaction to occur according to collision theory?
Reactant particles must collide with sufficient energy and proper orientation
How does increasing temperature generally affect an exothermic reaction’s equilibrium position?
It shifts the equilibrium to favor the endothermic (absorbing heat) side.
True or False: Catalysts increase the energy of the products.
False
True or False: In an endothermic reaction, the surroundings get warmer.
False
If a 4g metal object absorbs 500 J of heat and its temperature increases by 25°C, what is its specific heat capacity?
5
What is the effect of increasing concentration of reactants on the collision frequency?
It increases the number of collisions, thus speeding up the reaction
If pressure is increased on a system involving gases, what does Le Chatelier's principle predict will happen?
The equilibrium shifts toward the side with fewer moles of gas.
How does a catalyst affect the activation energy of a reaction?
It lowers the activation energy.
Give an example of an exothermic reaction.
Answers will vary
What is the formula to calculate heat gained or lost using specific heat?
Q=mcΔTQ
How does a catalyst influence the energy barrier of a reaction?
It lowers the activation energy, making it easier for collisions to lead to reactions.
When a system at equilibrium is disturbed, what does Le Chatelier's principle tell us about the direction of the shift?
The system shifts to counteract the disturbance and restore equilibrium.
Can a catalyst change the overall equilibrium position of a reaction? Why or why not?
No, because it only speeds up the rate.
Explain how the temperature change of the surroundings can help you determine whether a reaction is endothermic or exothermic.
If the surroundings become warmer during the reaction, it is exothermic because heat is released into the surroundings. If the surroundings become cooler, it is endothermic because heat is absorbed from the surroundings.
Does water have a high or low specific heat capacity?
High
Name two ways to increase the rate of a chemical reaction based on collision theory.
Increasing temperature and increasing reactant concentration (or adding a catalyst).
How does adding a catalyst affect the position of equilibrium?
It does not affect the position of equilibrium; it only speeds up reaching equilibrium.
What type of catalyst is used in biological systems to speed up reactions?
Enzymes