Chapter 2 Reaction Kinetics Review Honors Chemistry

Flashcards about Reaction Kinetics.

What is Chemical kinetics?

The investigation of the rate at which chemical reactions occur and the factors that affect them.

How is the average reaction rate calculated?

By using the initial and final point in time.

How is an instantaneous rate obtained?

Calculating the slope of a tangent line drawn to the graph at a particular time.

What tool is used to measure pressure and volume of gas?

Manometer measures the pressure of gas and eudiometer tube measures volume of gas.

What is the purpose of titration?

Determines concentration present at particular instances in time as the reaction proceeds.

What color does Fe+2(aq) and Cu+2(aq) have?

Fe+2(aq) has a yellow-orange color and Cu+2(aq) is blue

How can the rate of one species can be converted to another?

The mole ratio can be used to convert the rate of one species to another

When is a reaction heterogeneous?

Reactants are present in different states

What affect does increasing the surface area have on a solid?

Increasing the surface area of a solid increases the rate of a heterogeneous reaction

What affect does increasing the concentration of solute have on reaction rate?

Increasing the concentration of solute will increase the reaction rate

What affect does increasing the concentration or partial pressure of a gas have on reaction rate?

Increasing the concentration or partial pressure of a gas increases the reaction rate

What affect does increasing temperature have on particles?

Increasing temperature leads to particles striking more frequently and with more energy

Why are reactions between polyatomic ions in solution slower?

Reactions between polyatomic ions in solution are slower because of their complex structure.

What factors affect breaking and forming of bonds?

Ionization energy, electronegativity, ionic polarity, molecular polarity, size and complexity of structure

At room temperature what rate of reactants is greatest to slowest?

Water, gases, liquids and solids

What are catalysts?

Catalysts increase the rate of a reaction without being used up

What do catalysts provide?

An additional reaction mechanism with a lower activation energy, which results in an increased reaction rate

What does an inhibitor do?

Reduces the rate of a chemical reaction by combining with a reactant to stop it from reacting in its usual way

What are antagonists?

Drugs that act through inhibition

What is the rate of a reaction directly proportional to?

The rate of a reaction is directly proportional to the product of the concentrations of the reactants

What is the rate law?

Unique to each reaction

How do you find the overall reaction order?

The overall reaction order comes from adding x and y together

What does collision theory state reaction rates depend upon?

The number of collisions over time and the fraction of these collisions that succeed in producing products

What is activation energy (Ea)?

The minimum kinetic energy that the reacting species must have in order to react

What must be favorable for a successful collision to occur?

Geometric shape and collision geometry of reactants

What is energy stored as?

Chemical potential energy typically in chemical bonds

What is a change in enthalpy (∆H)?

A change in energy available as heat

What is enthalpy?

Potential energy that may be given off (-∆H) or absorbed as heat (+∆H)

What is bond energy?

Chemical potential energy stored in the bonds between atoms

When is a reaction endothermic?

If the energy absorbed to break bonds is greater than the energy released during bond formation

When is a reaction exothermic?

If more energy is released during bond formation than is absorbed during bond breaking

What does a thermochemical equation include?

Includes ∆H as part of the chemical equation

When does an activated complex form?

Reactant bonds are breaking and product bonds are forming

What is an activated complex?

Unstable, high-energy, transitory configuration of atoms that will decompose and form new, lower-energy, more stable products

What is a potential energy diagram?

Graphical representation of the energy changes that take place during a chemical reaction

What has more PE in an exothermic reaction?

The reactants have more PE than products

What has less PE than products in an endothermic reaction?

The reactants have less PE than products

What is the heat of reaction (∆H)?

The difference in PE between reactants and products

What is the activated complex found on a potential energy diagram?

The peak of the graph

What is the activation energy (Ea)?

The PE difference between the peak of the graph (activated complex) and the PE of the reactants

What is the activation energy (Ea)?

The amount of energy the reactant molecules must gain to form an activated complex