Chemistry Final (True/False)

Arrhennius acids produce OH- ions

False

Entropy has units of kJ/mol.

False; enthalpy has these units

You cannot predict the direction of equilibrium by determining the reaction quotient, Q, and comparing it to the equilibrium constant, K.

False.

"Heat" is a reactant in an endothermic reaction

True

A cation that is the counter ion of a strong base is pH neutral

True

A large pKa will result in a weaker acid

True

A negative sign for DeltaH indicates that the reaction is exothermic.

True

A nonspontaneous process will always occur when DeltaH is positive and Delta S is negative.

True

A nonspontaneous process will thermodynamically favor the reactants.

True

Acidity of oxyacids increases to the right across a period.

True

An endothermic reaction has a positive enthalpy of reaction

True

Aqueous solutions contain both H3O+ and OH- ions

True

Catalysts used to slow a reaction are called negative catalysts.

True

Concentrated acids may have a negative pH

True

Equilibrium can be predicted by utilizing to calculate free energy at non-standard conditions.

True

Equilibrium favors the left direction is K is less than 1.

True

Increasing temperature of a given reaction increases the kinetic energy of the molecules.

True

Increasing the temperature of a given reaction increases the kinetic energy of the molecules.

True

Kp is the equilibrium constant in regards to partial pressure.

True

Lewis bases are electron pair donors

True

Removing a reactant from a chemical equation in equilibrium will cause the reaction to shift left.

True

Spontaneous processes are irreversible

True

Strong acids donate practically all of their protons

True

Table salt, NaCl(s), dissolving in water will be an increase in entropy.

True

The absolute entropy of substances is always positive.

True

The activated complex is a temporary species formed by the reactant molecules as a result of the collision before they form the product.

True

The activated complex is the chemical species with partially formed and partially broken bonds.

True

The exchange of energy can be observed between the system and the surroundings.

True

The first law of thermodynamics states that the energy in the universe is conserved.

True

The frequency factor is the number of times that the reactant molecules will collide with one another to begin forming new bonds and breaking old bonds.

True

The law of mass action describes the equilibrium expression.

True

The rate determining step is the slow step.

True

The rate of a reaction is a measure of how fast the reaction makes products or uses reactants.

True

The rate of a zero order reaction is independent of the concentration of the reactants.

True

The transition state is the chemical species with partially formed and partially broken bonds.

True

The value of the equilibrium constant is independent of the initial amounts of the reactants and products.

True

When a strong acid is added to a buffer solution, the pH of the solution goes down slightly.

True

If the activation energy barrier is low then only a few reactant molecules in a sample may have enough energy to reach the transition state.

False

If the reaction quotient, Q, is equal to zero then the chemical reaction only contains reactants.

False

If you reverse a chemical equation, you must change the sign of the equilibrium constant.

False

In a Lewis-Acid reaction, the acid donates a pair of electrons to the base to form a covalent bond.

False

In a buffer solution, adding base will increase the acid concentration and decrease the base concentration.

False

Increases temperature decreases the activation energy

False

Increasing the temperature of a reaction will decrease the activation energy.

False

Molecules tend to react faster than ions

False

Reaction intermediates are found in the overall chemical reaction.

False

Strong acids are weak electrolytes

False

Stronger attraction means the stronger the acid or base

False

The conjugate base of HClO2 is H2ClO2

False

The entropy change on melting is always negative.

False

The larger the molar mass, the smaller the entropy.

False

The lower the percent ionization, the stronger the acid.

False

Heat is one way in which energy flows.

True

Homogenous catalysts react with a reactant molecule to help form a more stable activated complex.

True

If the change in moles (DeltaN) = 0, then Kc=Kp

True

In a reaction mechanism with a fast initial step, the rate determining step may contain intermediates.

True

In chemical kinetics, small molecules tend to react faster than large molecules.

True

For a process where the final condition is more random than the initial condition, DeltaS(system) is negative

False

A chemical reaction that has 3 reactant particles is said to be trimolecular.

False

A larger Ka value results in a stronger conjugate base

False

A negative sign for DeltaS(rxn) indicates that the reaction will definitely be spontaneous.

False

HBrO3 is less acidic than HBrO4

True

The farther the equilibrium position lies toward the products, the stronger the base or the acid.

True

The following reaction is spontaneous at standard state conditions at 25 degrees Celsius: 6CO2(g) + 6H2O(l) YIELDS C6H12O6(s) + 6O2(g) DeltaG = 2900kJ

True

The higher the pH, the more the basic the solution

True

The stronger the base, the larger the Kb value

True

What is lost by the surroundings is also gained by the system.

True

When DeltaG is positive, the reaction will be spontaneous in the reverse direction and K<1.

True

When a reaction has a fast initial step, the rate of the forward reaction equals the rate of the reverse reaction.

True

A nonspontaneous process can occur if work is done on the system. When this happens, the 2nd law of thermodynamics is violated.

False

Acids produce conjugate acids

False

Adding an inert gaseous reactant to a reaction mixture will increase its partial pressure and cause the equilibrium to shift right.

False

Adding heat to an endothermic reaction will result in an increase in the value of the equilibrium constant, K.

False

As the temperature increases in a chemical reaction, the rate will ultimately decrease.

False

Catalysts are made in an early mechanism step and consumed in a later step.

False

Elementary steps can be broken down into simpler steps.

False

Entropy change is favorable when the result is a more ordered system.

False

The exponent on each reaction in a rate law is determined by the coefficients in the chemical equation.

False

The higher the energy barrier, the higher the number of molecules that have sufficient energy to overcome it.

False

The pH of the salt, LiNO2 is neutral

False

The rate depends on the concentration of the products.

False

The rate law can be predicted from the overall reaction

False

The rate law cannot be determined from the balanced equation of an elementary step.

False

When the equilibrium constant, K, is 1, then DeltaG(rxn) will be negative.

False