Chemistry 2 Honors (Trey)
A reaction was found to be second order in carbon monoxide concentration. The rate of the reaction____ if the [CO] is doubled with everything else kept the same. a. doubles b. remains unchanged c. triples d. increase by a factor of 4 e. increase by a factor of 2
D
The order of a reaction is defined as the sum of powers of the concentration in the rate law.
True
The_____ law of thermodynamics states that entropy is always increasing. a. first b. second c. third d. fourth
b. second
Using Appendix C, calculate deltaS for the reaction below at 25°C and 1 atm. 3NO₂ (g) +H₂O (l) → 2HNO₃ (aq) + NO(g)
-289 J/K
Calculate the standard Gibbs free energy change for the following reaction at 25°C using Appendix C. CaCO₃(s) + 2HCl(g) --> CaCl₂(s) + CO₂(g) + H₂O(l)
-60.3 kJ/mol
A reaction has an average reaction rate of 0.33 min⁻¹. Calculate how many minutes it takes for the reaction concentration to decrease from 0.13 M to 0.088 M.
0.13 min
For a process. the enthalpy is 173kJ and its entropy change is 210.0 J/K. Calculate the Gibbs free energy change of the system at 55.0°C. Is the process spontaneous?
105 NOT spontaneous
Balance: ClO₃⁻ + I⁻ → I₂ + Cl₂ (acid solution)
12H⁺ + 2ClO₃⁻ + 10I⁻ → Cl₂ + 6H₂O + 5I₂
Using Appendix C calculate deltaS for the give reaction. 2Ag₂O(s) ---> 4Ag(s) + O₂(g)
132.6 J/K
Balance: MnO₄⁻ + Br⁻ → Mn²⁺ + Br₂ (acid solution)
16H⁺ + 2MnO₄⁻ + 10Br⁻ → 2Mn²⁺ + 8H₂O + 5Br₂
Balance: CN⁻ + Fe³⁺ → CNO⁻ + Fe²⁺ (basic solution)
2OH⁻ + CN⁻ + 2Fe³⁺ → CNO⁻ + 2Fe²⁺ + H₂O
Combine the steps to complete the complex. Cl + O³ → O₂ + ClO O₃ → O₂ + O ClO + O → Cl + O₂
2O₃ → 3O₂
For a process, the enthalpy change of a system is 1.25x 10² kJ and entropy change is 3000.0 J/K. Calsulate the Gibbs free energy change of the system at 17°C.
38 kJ/mol
Calculate the standard Gibbs free energy change for the following reaction at 400.0K. Assume standard enthalpy change of reaction and standard entropy does not change with temperature.
436 kJ/mol
Octane on reaction with chlorine produces octyl chloride and hydrogen chloride. Calculate the final concentration of octyl chloride when initial concentration of the product is 0.80 and the average reaction rate is 0.74 M/s. The initial time= 6.00s and the final time = 13.8s.
6.6M
Calculate the temperature at which deltaG=0 deltaH = 6.324kJ and deltaS = 75.87J/K.
83.35 K
Balance: Cu + NO₃⁻ → Cu²⁺ + NO (acid solution)
8H⁺ + 2NO₃⁻ + 3Cu → 2NO + 4H₂O + 3Cu²⁺
True/False 2H₂(g) + O₂(g) --> 2H₂O(g) For the reaction entropy is increasing.
False
True/False A single piece of newspaper burns faster than a shredded piece.
False
True/False If the temperature at which a reaction occurs increases, the number of collisions decreases.
False
True/False In thermodynamics, the universe is defined as the system minus its surroundings.
False
True/False Melting ice is an exothermic and there for spontaneous.
False
True/False Rusting is not a spontaneous process.
False
**Find #19-25 in Chapter 16 Reaction Rates Test**
Graph
2NO₂ → N₂O₂ Fast Step N₂O₂ + H₂ → N₂O + H₂O Slow Step N₂O + H₂O → N₂ + H₂O Fast Step Which of these reactions is the rate determining step?
N₂O₂ + H₂ → N₂O + H₂O Slow Step
2NO₂ → N₂O₂ Fast Step N₂O₂ + H₂ → N₂O + H₂O Slow Step N₂O + H₂O → N₂ + H₂O Fast Step The intermediate compounds for the mechanism is?
N₂O₂ and N₂O
List the oxidation and reduction reactions. NH₃ + NO₂ → N₂ + H₂O
Ox. 2NH₃ → N₂ + 6e⁻ Red. 2NO₂ + 8e⁻ → N₂
List the oxidation and reduction reactions. NaBr + Cl₂ → NaCl + Br₂
Ox. 2NaBr → Br₂ + 2e⁻ Red. Cl₂ + 2e⁻ → 2NaCl
Give Oxidizing and reduction agent and what is being oxidized and reduced. 3H₂S + 2HNO₃ → 3S + 2NO + 4H₂O
Ox. Agent HNO₃ Red. Agent H₂S Ox. S Red. N
Give Oxidizing and reduction agent and what is being oxidized and reduced. PbS + 4H₂O₂ → PbSO₄ + 4H₂O
Ox. Agent H₂O₂ Red. Agent PbS Ox. S Red. O
Give Oxidizing and reduction agent and what is being oxidized and reduced. 8NaI + 5H₂SO₄ → 4I₂ + H₂S + 4Na₂SO₄ + H₂O
Ox. Agent H₂SO₄ Red. Agent NaI Ox. I Re. S
Give Oxidizing and reduction agent and what is being oxidized and reduced. K₂Cr₂O₇ + 14HI → 2CrI₃ + 2KI + 3I₂ + 7H₂O
Ox. Agent K₂Cr₂O₇ Red. Agent HI Ox. I Red. Cr
List the oxidation and reduction reactions. Fe + F₂ → FeF₃
Ox. Fe → Fe³⁺ + 3e⁻ Red. F₂ + 2e⁻ → 2F⁻
**Find #14-16 on Chapter 16 Reaction Rates Test**
Table
**See Chapter 16 Reaction Rates Test Word Problems #1, 5, and 6**
Tables
True/False A spontaneous process is a physical or chemical change that occurs with no outside intervention.
True
True/False According to the rate law, the reaction rate is directly proportional to the molar concentration of the reactant.
True
True/False Free energy is the energy that is available to do work for reactions thta take place at constant pressure and temperature.
True
deltaS is negative for which reaction? a. 2SO2 (g) + O2 ---> 2SO3 (g) b. NH4Cl(s) ---> NH3 (g) + HCl (g) c. 2C (s) + O2 (g) --> 2CO2 (g) d. H2O (l) --> H2O (g)
a. 2SO2 (g) + O2 ---> 2SO3 (g)
A/An _______ is a substance that increases the rate of a chemical reaction. a. Catalyst b. Inhibitor c. Reactant d. Product
a. Catalyst
According to the first law of thermodynamics, the energy of the universe is _____. a. constant b. continually decreasing c. continually increasing d. zero
a. constant
A/An ______ exists in a physical sate different than that of the reaction it catalyzed. a. heterogeneous catalyst b. homogeneous catalyst c. inhibitor d. product
a. heterogeneous catalyst
For the reaction given below. deltaH = -1516kJ at 25 degrees Celsius and deltaS = -432.8 J/K at 25 degrees Celsius. This reaction is spontaneous ____________. SiH4 (g) + 2O2 (s) + 2H2O (l) a. only below a certain temperature b. only above a certain temperature c. at all temperatures d. at no temperatures e. cannot tell from the information available
a. only below certain temperatures
7. Which response contains all the processes below for which deltaS is negative and none for which deltaS is positive? I. CCL4 (l) ---> CCl4 (g) II. N2 (g) + H2 (g) ---> 2NH3 (g) III. I2 (g) ---> I2 (s) a. I and II b. II and III c. I and III d. I, II, and III
b. II and III
A/An _____ is a substance that slows down the rate of reaction. a. Catalyst b. Inhibitor c. Reactant d. Product
b. Inhibitor
From the information below, we can infer that___ is the rate-determining step. A reaction mechanism or the formulation of NO₂ is given as : a. 2NO₂ → N₂O₂ Fast Step b. N₂O₂ + H₂ → N₂O + H₂O Slow Step c. N₂O → N₂ + H₂O Fast Step
b. N₂O₂ + H₂ → N₂O + H₂O Slow Step
Which of the following statements about a catalyst is true? a. A catalyst can initiate a reaction b. a catalyst can accelerate a reaction c. a catalyst can be consumed during a reaction d. a catalyst can be changed during a reaction
b. a catalyst can accelerate a reaction
A ____ reaction is one that consists of two or more elementary reactions. a. simple b. complex c. single d. double
b. complex
Hydrogen iodide decomposes as 2HI ---> H₂ + I₂.The average reaction rate is expressed as: Average Rate = -(1Delta[HI]/ 2Delta(t)) The negative sign used in the rate expression indicates that: a. There are repulsive forces between the reactants b. the concentration of HI decreases with time c. The concentration of the reactants is less than that of the product d. the reaction rate is decreasing
b. the concentration of HI decreases with time
In the reaction 2A --> B the rate of reaction is quadrupled when the concentration of A is doubled. The rate expression of the reaction is r=k[A]ⁿ. define the value of n. a. 0 b. 1 c. 2 d. 3
c. 2
The standard Gibbs free energy of formation of ______ is zero. a. H2O (l) b. O (g) c. H2 (g) d. Al (l)
c. H2O (g)
Which response includes all the following processes that are accompanied by an increase in entropy, and only those processes? I. Boiling water II. freezing water III. N2 (g) + 3H2 (g) --> 2NH3 (g) IV. Br2 (l) --> Br2 (g) a. I and II b. III and IV c. I and IV d. II, III, and IV
c. I and IV
If the rate law for the reaction is first order in A and second order in B, then the rate law is rate= ________. 2A + 3B → products a. K[A][B] b. K[A]²[B]³ c. K[A]B]² d. K[A]²[B]
c. K[A]B]²
The rate law for a reaction is: rate=k[A][B]² Which of the following statements is false? a. the reaction is first order A b. The reaction is second order B c. The reaction is second order overall d. K is the reaction rate constant e. If [B] is doubled, the reaction rate will increase by a factor of 4
c. The reaction is second order overall
Of the following _____ will lower the activation energy for a reaction. a. Increasing the concentration of reactants b. raising the temperature of the reaction c. adding a catalyst for the reaction d. removing t\products as the reaction proceeds
c. adding a catalyst for the reaction
Which one of the following processes produces a decrease of the entropy of the system? a. dissolving sodium chloride in water b. sublimation of naphthalene c. dissolving oxygen in water d. explosion of nitroglycerine
c. dissolving of oxygen in water
A collision requires ____ to be effective. a. Only enough energy b. Favorable orientation c. enough energy and favorable orientation d. a reaction mechanism
c. enough energy and favorable orientation
Which one of the following processes produces a decrease in entropy of the system? a. boiling water to form steam b. dissolution of solid KCl in water c. freezing water to form ice d. melting ice to form water
c. freezing water to form ice
Consider the reaction below at 25 degrees Celsius for which deltaS = 16.1 J/K CH4 (g) + N2 (g) + 163.8 kJ --> HCN (g) + NH3 (g) Which one of the following statements describes the reaction? a. spontaneous at all temperatures b. spontaneous at relatively low temperatures only c. spontaneous at relatively high temperatures only d. nonspontaneous at all temperatures
c. spontaneous at relatively high temperatures only
Based on the relationship of entropy to the degree of disorder in a system, which response represents an increase in entropy? a. the freezing of water b. the condensation of steam c. sublimation of dry ice (solid CO2) d. the extraction of salts and pure water from sea water
c. sublimation of dry ice
Which of the following factors does NOT affect the rate of reaction? a. the amount of the reactants b. the physical state of the reaction c. the size of the container used d. temperature
c. the size of the container used
In which case must a reaction be spontaneous at all times? a. deltaH is positive and deltaS is positive b. deltaH = 0 and deltaS is negative c. deltaH is negative and deltaS = 0 d. deltaH is negative and deltaS is positive
d. deltaH is negative and deltaS is positive
The thermodynamic quantity that expresses the degree of disorder in a system is________. a. enthalpy b. internal energy c. external energy d. entropy
d. entropy
A process cannot be spontaneous if_______ a. it is exothermic, and there is an increase in disorder b. it is endothermic and there is an increase in disorder c. it is exothermic and there is a decrease in disorder d. it is endothermic and there is a decrease in disorder e. the entropy of the universe increases
d. it is endothermic and there is a decrease in disorder
The first law of thermodynamics states that________ a. all spontaneous process are accompanied by an increase in disorder b. energy is conserved during any process c. the amount of work done during a change is independent of the pathway of that change d. none of these
d. none of these
The sequence of steps that occurs in a reaction process is called the _______. a. Order of the reaction b. Rate Law c. Overall reaction d. Reaction mechanism
d. reaction mechanism
Which one of the following statements is not correct? a. when deltaG for a reaction is negative, the reaction is spontaneous b. when deltaG for a reaction is positive, the reaction is nonspontaneous c. when deltaH for a reaction is very positive, the reaction is not expected to be spontaneous d. when deltaH for a reaction is negative, the reaction is never spontaneous.
d. when deltaH for a reaction is negative, the reaction is never spontaneous.
Which of the following reactions has a positive entropy change? a. H2O (g) ---> H2O (l) b. BF3 (g) + NH3 ---> F3BNH3 (s) c. 2SO2 (g) + O2 (g) ---> 2SO3 (g) d. N2 (g) + 3H3 (g) ---> 2NH3 (g) e. 2NH4NO3 (s) ---> 2N2 (g) + 4H2 (g) + O2 (g)
e. 2NH4NO3 (s) ---> 2N2 (g) + 4H2 (g) + O2 (g)
The decomposition of hydrogen peroxide in the presence of iodide ions is of the first order. The reaction is 2H₂O₂ → 2H₂O + O₂ Write the rate law for this reaction and calsulate the concentration of H₂O₂ when the rate of the reaction is 1.12x10⁻²M/s and the rate constant is 1.01x10⁻²s⁻¹.
r = k[H₂O₂] [H₂O₂] = 1.11 M
