Reaction Rates
What is collision theory?
atoms, ions, and molecules can react to form products when they collide with sufficient energy
What's the difference between the endo and exo reactions in the case of a diagram
Endothermic reactions, the products have a higher energy level than the reactants
Exothermic reactions,The reactants have a higher energy level than the products
Are catalysts consumed in the experiment?
No
What does Le Chatelier’s principle state?
if an equilibrium is disturbed by changing the conditions, the equilibrium shifts to counteract the change to reestablish an equilibrium
What is neutral on the pH scale?
The neutral is 7
Can speeding-up the reaction rate by increasing concentration increase percent yield?
yes
What is the highest point of the Energy Diagram?
Activated Complex
How does a catalyst affect activation energy?
The catalyst lowers the energy of the transition state for the reaction. Since the activation energy is the difference between the transition state and the reactant energy, lowering the transition state energy also lowers the activation energy.
What does it mean if the equilibrium is shifted to the left?
This means that there are more products than reactants in that moment (in the situation that there are reactants being dispersed) so the equilibrium is shifted to the left so that there can be more reactants to produce to make the system equal.
Acids are measured by the concentration of…
Protons and/or H3O+ or H+
What is the rate law?
r = K[reactant 1]x[reactant 2]y
How are forward and reverse reactions related?
The reverse reaction is the opposite of the forward reaction. So if the forward reaction is exothermic, the reverse reaction will be endothermic.
What is the relation of the catalyst to the forward/reverse reaction?
Decreases activation energy for both, making it easier to happen
What happens when you add more reactants to a reaction according to Le Chatelier’s principle?
Shifts the equilibrium to the right, to the products.
What do acids and bases do with hydrogen ions?
Acids produce Hydrogen ions while bases accept hydrogen ions.
If the concentration of the reactant is tripled, the rate of the reaction is 9 times faster. What is the order of the reaction?
second order or 2
What does ΔH represent in an energy diagram?
change in bond energy
How do catalysts help keep us alive?
By allowing chemical reactions to occur at temperatures our cells can handle.
Also they increase the rate of reaction by holding molecules.
How does temperature affect an endothermic reaction?
Increases forward reaction rate to increase product.
What happens when acids and bases are mixed together?
when acids and bases are mixed together correctly they can become naturalized and form a salt and water
If you wanted to change the K value of a system in equilibrium what must you change?
temperature
Will the enthalpy (energy change) be positive or negative for an endothermic reaction?
endothermic = + (bonds gain energy)
exothermic = - (bonds lose energy)
What effect do catalysts have on the pressure needed for a reaction?
Decrease the amount of pressure needed for the reaction to take place.
How does changing pressure affect equilibrium?
When there is an increase in pressure, the equilibrium will shift towards the side of the reaction with fewer moles of gas. When there is a decrease in pressure, the equilibrium will shift towards the side of the reaction with more moles of gas.
Identify the conjugate acid: H2O + NH3 -->NH4+ + OH-
NH4+
The base is the NH3