FINAL Flashcards
What is a combination reaction?
Is a reaction in which two or more substances combine to form a single new substance Example: A+B→AB
What is a decomposition reaction?
A reaction in which a compound breaks down into two or more simpler substances. Example: AB→A+B
What is a displacement reaction?
Where an atom or a set of atoms are displaced by another atom in a molecule. Example: A + B-C → A-C + B
What is an exchange reaction?
It is where the elements that were partners on one side are then interchanged and switch partners on the other side. Example: AgNO3 + NaCl → AgCl + NaNO3
What is a combustion reaction?
a reaction in which a substance reacts with oxygen, releasing energy in the form of light and heat.
Identify the category of the following reaction.
4HNO3 → 4NO2 + 2H2O + O2
a.Combination reaction
b.Decomposition reaction
c.Single-replacement reaction
d.Double-replacement reaction
b. Decomposition reaction
What is a redox reaction?
A reaction that involves a transfer of electrons from one reactant to another
What is a nonredox reaction?
A reaction where there are no transfer of electrons from one reactant to another
What is the difference between oxidation and reduction in a redox reaction?
Oxidation: A reactant loses one or more electrons
Reduction: A reactant gains one or more electrons
What is an oxidizing agent and what is a reducing agent in redox reactions?
Oxidizing agent: the substance that gained electrons
Reducing agent : the substance that lost electrons
What is the molecular collision theory?
It is a theory that all molecules, ions, or atoms must come into contact (collide) with one another for any chemical change to occur
What is activation energy?
The combined kinetic energy that occurs when particles collide that they must have in order for their collision to be a chemical reaction
What is collision orientation?
It is where molecules or atoms or ions must collide in a certain way in order to successfully to get a product. If not then no product is produced
What are the three factors necessary for a
chemical reaction to occur?
a.Proper temperature, pressure, and concentration
b.Proper temperature, pressure, and low activation energy
c.Proper temperature, low activation energy, and proper
orientation of colliding particles
d. Molecular collisions, low activation energy, and proper
orientation of particles
d. Molecular collisions, low activation energy, and proper
orientation of particles
How can you tell the difference between exothermic chemical reactions and endothermic chemical reactions?
Exothermic chemical reactions: Energy is released as a product, and products are more stable than reactants
Endothermic chemical reactions: Input of energy is needed for the reaction to occur. Energy is the reactant. Additional energy must be put in so the reaction process can happen. Products are less stable than reactants
What are some examples of exothermic chemical reactions, and endothermic chemical reactions?
Exothermic chemical reactions: Burning fuel
Endothermic chemical reactions: Photosynthesis of plants
Which of the following statement(s) is(are) correct?
a.During an exothermic reaction, the average energy of the products is
higher than the average energy of the reactants.
b.During an endothermic reaction, the average energy of the products
is lower than the average energy of the reactants.
c.During an exothermic reaction, the average energy of the products is lower than the average energy of the reactants.
d.Both (a) and (b)
c.During an exothermic reaction, the average energy of the products is lower than the average energy of the reactants.
How does the reactant concentration affect the reaction rate?
When you increase the concentration of the reactant it increases the reaction rate. this is because it creates more molecules and when you have more molecules more collisions occur
What is physical nature of reactants?
It is where the physical state of a reactant and the particle size affects the reaction rate
Between the physical states of matter. Which ones make the reaction rate go slow? and what make the reaction rate go fast?
- The slowest are between solids
- The next fastest are between liquids
- And the fastest are between gasses
How does temperature affect the reaction rate?
As the temperature rises the reactant rate increases. This is because the molecules gain more speed and cause more collisions
How does the presence of catalysts affect the reaction rate?
It increases the reaction rates by providing different pathways that have lower activation energies
What are the catalysts called in human bodies?
Enzymes
What is the function of a catalyst in a chemical
reaction?
a.It increases the rate of the reaction by increasing the activation
energy.
b.It increases the rate of the reaction by decreasing the activation
energy.
c.It decreases the rate of the reaction by increasing the activation
energy.
d.It decreases the rate of the reaction by decreasing the activation
energy.
b.It increases the rate of the reaction by decreasing the activation
energy.
What is a oxidizing agent?
The element that gains electrons and helps the other element lose electrons
What is a reducing agent?
The element that loses electrons and helps the other element gain electrons
What is the reversible chemical reaction?
Where the reactions form the products and simultaneously the products form the reactants
What is chemical equilibrium?
Where forward and reverse chemical reactions go at the same rate. The concentrations of the reactants and products no longer change
What do the brackets mean in the equilibrium constant expression?
The molar concentration
Where do the products ALWAYS GO in the equilibrium constant expression?
On top as the numerator
Where do the reactants ALWAYS GO in the equilibrium constant expression?
On bottom as the denominator
If Keq is greater than 1 are there more products or reactants?
More products
If Keq is Less than 1 are there more products or reactants?
More reactants
If more products are produced than reactants, which way does the equilibrium shift?
To the right
If more reactants are produced than products, which way does the equilibrium shift?
To the left
What is the Le Châtelier’s Principle?
If a stress is applied to a system at equilibrium the system will readjust in the direction that best reduces the stress on the system (Left or Right).
What type of things change Keq And what things don’t change Keq?
Things that change Keq:
Temperature
Things that Don’t change Keq:
* Reactant or product concentration
* Pressure (only gas reactions)
* Catalysts (including enzymes!)
What is the concentration of change in the equilibrium system?
If the concentration of a substance is increased, the reaction that consumes that substance is favored, and the equilibrium shifts away from that substance
What is the pressure of change in the equilibrium system?
increasing the pressure shifts the equilibrium toward the side with fewer
moles of gas.
Decreasing the pressure shifts the equilibrium
towards the side with greater number of moles.
What is the addition of catalysts in the equilibrium system?
It just speeds up the process as a whole and no shifting happens
What is an Arrhenius acid?
Hydrogen-containing
compound that produces H+ ions in solution
What is an Arrhenius base?
Hydroxide-containing
compound that produces OH– ions in solution
What kind of compound does Ionization use?
Molecular compound
What kind of compound does dissociation use?
Ionic compound
What is ionization?
Is which individual positive and negative ions are produced from a molecular compound that is dissolved in a solution
What is dissociation?
Is which individual positive and negative ions are released from an ionic compound (a metal and a nonmetal) that is dissolved in a solution