Chem Test, Kinetics, 8AP Chemistry Possible Questions Bank

After a certain pesticide compound is applied to crops, its decomposition is a first-order reaction with a half-life of 5656 days. What is the rate constant, kk, for the decomposition reaction?

0.012day−1

X → products Pure substance X decomposes according to the equation above. Which of the following graphs indicates that the rate of decomposition is second order in X ?

1/x going up

Consider the following data for the reaction MX2 → products Determine the order of this reaction. 1. zero order 2. one half order 3. first order 4. second order 5. cannot be determined

4

Consider the following reaction 2 N2O(g) → 2 N2(g) + O2(g) rate = k [N2O] . For an initial concentration of N2O of 0.50 M, calculate the concentration of N2O remaining after 2.0 min if k = 3.4 × 10−3s−1 . 1. 0.50 M 2. 0.17 M 3. 0.55 M 4. 0.33 M 5. 0.66 M

4

Which contains an element in a +1 oxidation state

E (Cu2O)

A. H2O B. NH3 C. BH3 D. CH4 E. SiH4 Which has a trigonal-pyramidal molecular geometry​

B

The rate of formation of oxygen in the following reaction is 2.28 M/s. 2 N2O5(g) → 4 NO2(g) + O2(g) What is the rate of formation of NO2? 1. 9.12 M/s 2. 2.28 M/s 3. 4.56 M/s 4. 1.14 M/s 5. 0.57 M/s

1

What is the rate law for this reaction? 1. None of these 2. rate = k [H2] [NO] 3. rate = k [H2] [NO]2 4. rate = k [H2]/ 2[NO] 5. rate = k[H2]/[NO]2 6. rate = k[H2]/[NO]

3

A mechanism for the decomposition of ozone (2 O3 → 3 O2) is O3 → O2 + O O + O3 → O2 + O2 What is the molecularity for the first and second elementary reactions? 1. 2 and 1 2. 1 and 2 3. None of these 4. 2 and 2 5. 1 and 1

2

Consider the reaction 2 A(g) + B(g) → C(g) + D(g). When [A] = [B] = 0.10 M, the rate is 2.0 M/s; for [A] = [B] = 0.20 M, the rate is 8.0 M/s; and for [A] = 0.10 M, [B] = 0.20 M, the rate is 2.0 M/s. What is the rate law? 1. rate = k [A] [B]0 2. rate = k [A]2 3. rate = k [A] 4. rate = k [A] [B] 5. rate = k [B]2

2

How many protons neutrons and electrons are in an 56/26 Fe atom?

26 protons, 30 neutrons and 26 electrons

Determine the overall balanced equation for a reaction having the following proposed mechanism Step 1: B2 + B2 −→ E3 + D slow Step 2: E3 + A −→ B2 + C2 fast and write an acceptable rate law. 1. A + B2 −→ C2 + D; R = k [A][B2] 2. E3 + A −→ B2 + C2; R = k [E3] [A] 3. A + B2 −→ C2 + D; R = k [B2]2 4. B2 + B2 −→ E3 + D; R = k [B2]2

3

An unknown acid is dissolved in 25mL of water and titrated with 0.1000 M NaOH. The results are shown in the titration curve above. Which of the following could be the unknown acid? A. pKa = 2.6 B. pKa = 3.8 C. pKa = 4.9 D. pKa = 7.5 E. pKa = 9.3

B

Atoms of Mg combine with atoms of F to form a compound. Atoms of which of the following elements combine with atoms of F in the same ratio A. Li B. Ba C. Al D. Cl E. Ne

B

Hone the equation above is balanced and the coefficients are reduced to lowest whole number terms, what is the coefficient of H2O A. 1 B. 2 C. 3 D. 4 E. 5

B

Resonance is most commonly used to describe the bonding in molecules of which of the following A. CO₂ B. O₃ C. H₂O D. CH₄ E. SF₆

B

2 NO(g) + O2(g) → 2 NO2(g) A possible mechanism for the overall reaction represented above is the following: (1) NO(g) + NO(g) → N2O2(g) slow (2) N2O2(g) + O2(g) → 2 NO2(g) fast Which of the following rate expressions agrees best with this possible mechanism? (A) Rate = k[NO]2 (D) Rate = k[NO]2[O2] (B) Rate = k[NO] (E) Rate = k[N2O2][O2] [O2] (C) Rate = k[NO]2 [O2]

A

26. According to the rate law for the reaction, an increase in the concentration of hydronium ion has what effect on this reaction? (A) The rate of reaction increases. (B) The rate of reaction decreases. (C) The value of the equilibrium constant increases. (D) The value of the equilibrium constant decreases. (E) Neither the rate nor the value of the equilibrium constant is changed.

A

A student is trying to determine the heat of reaction for the acid-base neutralization reaction represented above. The student uses 0.50 M NaOH and 0.50 M HCl solutions. Which of the following situations, by itself, would most likely result in the LEAST error in the calculated value of the heat of reaction A. The thermometer was incorrectly calibrated and read 0.5 C degree too high during the procedure B. The volume of the acid solution added to the calorimeter was actually 1.0 mL less than what was recorded C.The calorimeter was poorly insulated, and some heat escaped to the atmosphere during the procedure D. The actual molarity of the base solution was 0.53 M but was recorded as 0.50 M E. The final temperature of the mixture was taken before the contents of the calorimeter had reached thermal equilibrium

A

A. H2O B. NH3 C. BH3 D. CH4 E. SiH4 Which has two lone pairs of electrons

A

For the reaction 2H2 + 2NO --> N2 + 2H2O The rate law is rate = k[H2][NO]2. At a given temperature, what is the effect on the reaction rate if the concentration of H2 is doubled and the concentration of NO is halved? a. The rr is halved b. The rr is unchanged c. the rr is doubled d. the rr increases eightfold

A

Gases generated in a chemical reaction are sometimes collected by the displacement of water, as shown above. Which of the following gases can be quantitatively collected by this method? A. H2 B. CO2 C. HCl D. SO2 E. NH3

A

H3AsO4 + 3I−+ 2 H3O+ H3AsO3 + I3− + H2O The oxidation of iodide ions by arsenic acid in acidic aqueous solution occurs according to the stoichiometry shown above. The experimental rate law of the reaction is: Rate = k [H3AsO4] [I−] [H3O+] 25. What is the order of the reaction with respect to I−? (A) 1 (B) 2 (C) 3 (D) 5 (E) 6

A

If 50 mL of 1.0 M NaOH is diluted with distilled water to a volume of 2.0 L, the concentration of the resulting solution is A. 0.0025 M B. 0.050 M C. 0.10 M D. 0.50 M E. 1.0 M

A

KHP is used as a primary standard for determining the concentration of a solution of NaOh by titration. If the KHP has not been dried before weighing, the calculated molarity of the NaOH would be A. higher than the actual value since water is included in the mass B. higher than the actual value, since the presence of water requires a larger volume of titrant C. lower than the actual value, since NaOH absorbs water D. unaffected, since KHP is a strong acid E. unaffected, since water is routinely added before titration

A

The steps below represent a proposed mechanism for the catalyzed oxidation of CO by O3 step 1: NO2 + CO -> NO + CO2 step 2: NO + O3 -> NO2 + O2 What are the overall products of this reaction? a. CO2 and O2 b. NO and CO2 c. NO2 and O2 d. NO and O2

A

Time (days) 0 1 2 3 4 5 6 7 ... 10 ... 20 % Reactant Remaining 100 79 63 50 40 31 25 20 ... 10 ... 1 A reaction was observed for 20 days and the percentage of the reactant remaining after each day was recorded in the table above. Which of the following best describes the order and the half-life of the reaction? Reaction Order Half-life(days) (A) First 3 (B) First 10 (C) Second 3 (D) Second 6 (E) Second 10

A

Which of the following is a correct statement about the reaction order? a. reaction order can be determined only by the experiment b. reaction order can be determined only from the coefficients of the balanced equation for the reaction c. reaction order increases with increasing temperature d. a second order reaction must involve at least two different compounds as reactants

A

Which of the following lists Mg, P and Cl in order of increasing atomic radius? A. Cl < P < Mg B. Cl < Mg < P C. Mg < P < Cl D. Mg < Cl < P E. P < Cl < Mg

A

Which of the following molecules contains exactly three sigma bonds and two pi bonds A. C₂H₂ B. CO₂ C. HCN D. SO₃ E. N₂

A

2 Nh3 → 3 H2 + n2 ∆H + 92 kj/mol According to the information above what is the standard enthalpy of formation ∆H for NH3 at 298K A. -92 B. -46 C. 46 D. 92 E. 184

B

36. The initial-rate data in the table above were obtained for the reaction represented below. What is the experimental rate law for the reaction? (A) rate = k[NO] [O2] (B) rate = k[NO] [O2]2 (C) rate = k[NO]2 [O2] (D) rate = k[NO]2 [O2]2 (E) rate = k[NO] / [O2]

B

49. The isomerization of cyclopropane to propylene is a first-order process with a half-life of 19 minutes at 500 °C. The time it takes for the partial pressure of cyclopropane to decrease from 1.0 atmosphere to 0.125 atmospheres at 500 °C is closest to... (A) 38 minutes (B) 57 minutes (C) 76 minutes (D) 152 minutes (E) 190 minutes

B

57. rate = k[X] For the reaction whose rate law is given above, a plot of which of the following is a straight line? (A) [X] versus time (B) ln [X] versus time (C) 1/(X) verses time (D) [X] versus 1/time (E) ln [X] versus 1/time

B

A molecular solid coexists with its liquid phase at its melting point. The solid-liquid mixture is heated, but the temperature does not change while the solid is melting. The best explanation for this phenomenon is that the heat absorbed by the mixture A. is lost to the surroundings very quickly B. is used in overcoming the intermolecular attractions in the solid C. is used in breaking the bonds within the molecules of the solid D. causes the nonbonding electrons in the molecules to move to lower energy levels E. causes evaporation of the liquid, which has a cooling effect

B

A reaction is first order with respect to [X] and second order with respect to [Y]. When [X] = 2M and [Y] = 2M, the rate is 8M/min. The value of the rate constant, including correct units is a. 1 M-1 min -1 b. 1M -2 min-1 c. 2M 1 min -1 d. 2M-2 min 01

B

Step 1: Ce4+ + Mn2+ Ce3+ + Mn3+ Step 2: Ce4+ + Mn3+ Ce3+ + Mn4+ Step 3: Mn4+ + Tl+ Tl3+ + Mn2+ 23. The proposed steps for a catalyzed reaction between Ce4+ and Tl+ are represented above. The products of the overall catalyzed reaction are... (A) Ce4+ and Tl+ (B) Ce3+ and Tl3+ (C) Ce3+ and Mn3+ (D) Ce3+ and Mn4+ (E) Tl3+ and Mn2+

B

The decomposition of peroxide is first order. Which of the following statements are true about the graph below a. the y axis represents [h2o2] and the slope = -k b. the y axis represents ln[h2o2] and the slope=-k c. the y axis represents 1/[h2o2] and the slope=-k d. the y axis represents ln[h2o2] and slope= 1/k

B

The graph to the right shows the results of a study of the reaction of X with a large excess of Y to yield Z. The concentrations of X and Y were measured over a period of time. According to the results, which of the following can be concluded about the rate of law for the reaction under the conditions studied? (A) It is zero order in [X] (B) It is first order in [X]. (C) It is second order in [X]. (D) It is the first order in [Y]. (E) The overall order of the reaction is 2.

B

The reaction represented above is observed to proceed spontaneously to the right in aqeous solution. In this system the strongest base is A. So4² B.CO₃² C. H₂O D. HCO³ E. HSO⁴

B

Which of the following is NOT an accepted name for the formula given A. CH₃OH.. methanol B. CuO .. copper (i) oxide C. FeCl₃ ... iron (iii) chloride D. H₂SO₄ ... sulfuric acid E. SrCO₃ ... strontium carbonate

B

Which of the following statements is a correct interpretation of the data regarding how the order of the reaction can be determined? a. The reaction must be first order because there is only one reactant species b. The reaction is first order if the plot of ln[H2O2] vs time is a straight line c. The reaction is first order if the plot of 1/[H2O2] vs time is a straight line d. The reaction is second order because 2 is the coefficient of H2O2 in the chemical equation

B

The reaction between a Broasted-Lowry acid and a Bronsted-Lowry Base

B (C2H3O2- + H3O+ --> HC2H3O2 + H2O)

Which flask contains the smallest number of moles of gas

B (High temp, low pressure)

In which flask do the molecules have the greatest average speed

B (High temp, low pressure)

28. 2 A(g) + B(g) ⇄ 2 C(g) When the concentration of substance B in the reaction above is doubled, all other factors being held constant, it is found that the rate of the reaction remains unchanged. The most probable explanation for this observation is that... (A) the order of the reaction with respect to substance B is 1. (B) substance B is not involved in any of the steps in the mechanism of the reaction. (C) substance B is not involved in the rate-determining step of the mechanism, but is involved in subsequent steps. (D) substance B is probably a catalyst, and as such, its effect on the rate of the reaction does not depend on its concentration. (E) the reactant with the smallest coefficient in the balanced equation generally has little or no effect on the rate of the reaction.

C

58. (CH3)3CCl(aq) + OH− (CH3)3COH(aq) + Cl− For the reaction represented above, the experimental rate law is given as follows: Rate = k [(CH3)3CCl] If some solid sodium solid hydroxide is added to a solution that is 0.010-molar in (CH3)3CCl and 0.10-molar in NaOH, which of the following is true? (Assume the temperature and volume remain constant.) (A) Both the reaction rate and k increase. (B) Both the reaction rate and k decrease. (C) Both the reaction rate and k remain the same. (D) The reaction rate increases but K remains the same (E) The reaction rate decreases but k remains the same.

C

82. Nitramide, N2H2O2, decomposes slowly in aqueous solution. This decomposition is believed to occur according to the reaction mechanism above. The rate law for the decomposition of nitramide that is consistent with this mechanism is given by which of the following? (A) Rate = k [N2H2O2] (B) Rate = k [N2H2O2] [H+] (C) Rate = (k [N2H2O2]) / [H+] (D) Rate = (k [N2H2O2]) / [N2HO2−] (E) Rate = k [N2H2O2] [OH−]

C

A 0.10 M solution of a weak monoprotic acid has a pH equal to 4.0. The ionization constant ka of the acid is A. 1 x 10^-3 B. 1 x 10^-4 C. 1 x 10^-7 D. 1 x 10^-8 E. 1 x 10^-9

C

A 2L sample of N2 and a 1 L sample of Ar each originally at 1 atm and O C are combined in a 1L tank. if the temperature is held constant, what is the total pressure of the gases in the tank? A. 1 atm B. 2 atm C. 3 atm D. 4 atm E. 5 atm

C

A student prepares a solution by dissolving 60.00g of glucose in enough distilled water to make 250.0mL of solution. The molarity of the solution should be reported as A. 12.01 M B. 12.0 M C. 1.332 M D. 1.33 M E. 1.3 M

C

A. H2O B. NH3 C. BH3 D. CH4 E. SiH4 Which has a central atoms with less than an octet of electrons

C

A. H2O B. NH3 C. BH3 D. CH4 E. SiH4 Which is predicted to have the largest bond angle

C

For the reaction below, the rate= k[(CH3)3CCl]. if some NaOH (s) is added to a solution that is 0.010 M in (CH3)3CCl and 0.10 M in NaOH, which of the following is true, assuming volume and temperature remain constant? (CH3)3CCl _ OH -> (CH3)3COH + Cl- a. both the reaction rate and k increase b. both the reaction rate and k decrease c. both the reaction rate and k remain the same d. the reaction rate increases but k remains the same

C

For the reaction: 5O2 (g) + 4NH3 (g) --> 4NO(g) + 6H2O (g) If NH3 is being consumed at a rate of 0.5, at what rate is H2O being formed? a. 0.33 b. 0.5 c. 0.75 d 3.0

C

The decomposition of ammonia to the elements is a first order reaction with a half life of 200s at a certain temperature. how long will it take the partial pressure of ammonia to decrease from 10 atm to 0.625 atm a. 200s b. 400 c. 800 d. 1000

C

The half life of iodine 131 is 8.02 days. how long will it take for 80% of the sample to decay? a. 2.6 days b 13 c. 19 d. 32

C

The role of a catalyst in a chemical reaction is to A. decrease the amount of reactants that must be used B. lower the activation energy for the reaction C. supply the activation energy required for the reaction to proceed D. increase the amounts of products formed at equilibrium E. increase the entropy change for the reaction

C

Using the method of inital rates and the data below what is the rate law for A+B+C-> D+E a. rate= k[a][b][c] b. rate=k[a]2[b]2[c]2 c. rate=k[a][b]2[c]-1 d. rate=k[a]2[b][c]-1

C

What is the empirical formula of an oxide of chromium that is 48 percent oxygen by mass A. CrO B. CrO2 C. CrO3 D. Cr2O E. Cr2O3

C

Which of the following are reasons why reaction rates increase as temperature increases? I. Collisions are more frequent between molecules at higher temperatures II. A greater fraction of collisions have sufficient energy to exceed Ea at higher temperatures III. Reactant concentrations are higher at higher temperatures a. I only b. II only c. I and II d. I, II, III

C

Which of the following is a correct statement about reaction order? (A) Reaction order can only be a whole number (B) Reaction order can be determined only from the coefficients of the balanced equation for the reaction (C) Reaction order can be determined only by experiment (D) Reaction order increases with increasing temperature (E) A second-order reaction must involve at least two different compounds as reactants

C

Which of the following is an isomer of CH₃OCH₃ A. CH₃CH₃ B. CH₃COOH C. CH₃CH₂OH D. CH₃CH₂CH₃ E. CH₃CH₂OCH₂CH₃

C

Which of the following substances is a strong electrolyte when dissolved in water A. sucrose B. ethanol C. sodium nitrate D. acetic acid E. ammonia

C

Which flask contains the sample with the greatest density

C (Highest pressure)

17. Relatively slow rates of chemical reaction are associated with which of the following? (A) The presence of a catalyst (B) High temperature (C) High concentration of reactants (D) Strong bonds in reactant molecules (E) Low activation energy

D

According to the standard reduction potentials given above, what is the standard cell potential for the reaction represented below? A. -1.74 V B. -0.86 V C. 1.74 V D. 2.46 V E. 4.06 V

D

C3H8 + 5O2 --> 3 Co2 + 4 H2O In the reaction represented above, what is the total number of moles of reactants consumed when 1.00 mole of Co2 is produced? A. 0.33 mol B. 1.33 mol C. 1.50 mol D. 2.00 mol E. 6.00 mol

D

For an experiment, a student needs 100 mL of 0.4220 M NaCl. If the student starts with NaCl and distilled water, which of the following pieces of laboratory glassware should the student use to prepare the solution A. 25 mL volumetric pipet B. 100 mL Erlenmeyer flask C. 100 mL graudated cylinder D. 100 mL volumetric flask E. 1 L beaker

D

H2 + F2→ 2HF In the reaction represented above, what mass of HF is produced by the reaction of 3.0 x 10^23 molecules of H2 with excess F2 A. 1 g B. 4 g C. 10 g D. 20 g E. 40 g

D

High solubility of an ionic solid in water is favored by which of the following conditions I. The existence of strong ionic attractions in the crystal lattice II. The formation of strong ion-dipole attractions III. An increase in entropy upon dissolving A. I B. I and II C. I and III D. II and III E. I, II, and III

D

In an insulated cup of negligible heat capacity, 50 g of water at 40 C mixed with 30 g of water at 20 C. The final temperature of the mixture is closest to A. 22 C B. 27 C C. 30 C D. 33 C E. 38 C

D

In order to determine the order of the reaction below: X + 2Y --> XY2 In trial 2 which of the reactions would be consumed more and why a. X b/c higher molar concentration b. X because the reaction is second order in X c. Y because the reaction is in second order in Y d. Y because the rate of disappearance will be double that of X

D

Permanganate and oxalate ions react in an acidified solution according to the balanced equation above. How many moles of Co2 are produced when 20 mL of acidified 0.20 M KmnO₄ solution is added to 50 mL of 0.10 M Na2C2O4 A. 0.0040 B. 0.0050 C. 0.0090 D. 0.010 E. 0.020

D

Rate = k[M][N]2 The rate of a certain chemical reaction between substances M and N obeys the rate law above. The reaction is first studied with [M] and [N] each 1 × 10−3 molar. If a new experiment is conducted with [M] and [N] each 2 × 10−3 molar, the reaction rate will increase by a factor of ... (A) 2 (B) 4 (C) 6 (D) 8 (E) 16

D

When a 3.22 g sample of an unknown hydrate of sodium sukfate, Na2So4 * x H2O is heated, H2O is driven off. The mass of the anhydrous Na2SO4 that remains is 1.42. The value of x in the hydrate is A. 0.0013 B. 1.8 C. 6.0 D. 10 E. 20

D

Which of the following molecules contains polar covalent bonds but is a nonpolar molecule? A. Ch3Cl B. CH2Cl2 C. NH3 D. CCl4 E. N2

D

Which of the following must be true for a reaction for which the activation energy is the same for both the forward and the reverse reactions? (A) A catalyst is present. (B) The reaction order can be obtained directly from the balanced equation. (C) The reaction order is zero. (D) ΔH° for the reaction is zero. (E) ΔS° for the reaction is zero.

D

Which of the following rate laws has a rate constant with units of L2 mol-2 s-1 a. rate = K[A] b. rate = k[A][B] c. rate= k[A]2 d. rate = k[A][B]2

D

Which of the following substances has the greatest solubility in C5H12 at 1 atm A. SiO2 B. NaCl C. H2O D. CCl4 E. NH3

D

A 0.20 mol sample of MgCl2 and a 0.10 mol sample of KCl are dissolved in water and diluted to 500 mL. What is the concentration of Cl- in the solution? A. 0.15 B. 0.30 C. 0.50 D. 0.60 E. 1.0

E

C2H4 is reduced by H2 in the presence of a solid platinum catalyst, as represented by the equation above. Factors that could affect the rate of the reaction include which of the following I. Changes in the partial pressure of H2 II. Changes in the particles size of the platinum catalyst III. Changes in the temperature of the reaction system A. III only B. I and II C. I and III D. II and III E. I, II and III

E

For which of the following reaction mixtures at equlibrium would reducing the volume of the container at constant temperature cause the equilibrium to shift towards the products? A. SrCO3 ⇌ SrO + Co2 B. C + Co2 ⇌ 2 CO C. Co + H2O ⇌ Co2 + H2 D. PCl5 ⇌ Pcl3 + Cl2 E. 2 No2 ⇌ N2O4

E

If the oxygen isotope ²⁰O has a half-life of 15 seconds, what fraction of a sample of pure ²⁰O remains after 1.0 minute A. 1/2 B. 1/4 C. 7/30 D. 1/8 E. 1/16

E

N2O5 ⇌ 2No2 + 1/2 O2 The equilibrium constant for the gas phase reaction above is 95 ar 25 C. What is the value of the equilibrium constant for the following reaction at 25C O2 + 4NO2 ⇌ 2 N2O5 A. (95)² B. 95 C. (95)¹/² D. 1/95 E. 1/(95)²

E

The percentage of silver in a solid sample is determined gravimetrically by converting the solver Ag and precipiatating it as silver chloride. Failure to do which of the following could cause errors in the analysis I. Account for the mass of the weighing paper when determining the mass of the sample II. Measure the temperature during the precipitation reaction III. Wash the precipitate IV. Heat the AgCl precipitate to constant mass A. I only B. I and II C. I and IV D. II and III E. I, II and IV

E

When 4.00 mol of each of X and Y are placed in a 1.00 L vessel and allowed to react at constant temperature according to the equation above, 6.00 mol of Z is produced. What is the value of the equilibrium constant Kc A. 3 B. 6 C. 8 D. 16 E. 36

E

Which of the following elements has the largest first ionization energy A. Li B. Be C. B D. C E. N

E

Which of the following is the electron configuration of an excited atom that is likely to emit a quantum of energy? A. 1s²2s²2p⁶3s²3p¹ B. 1s²2s²2p⁶3s²3p⁵ C. 1s²2s²2p⁶3s² D. 1s²2s²2p⁶3s¹ E. 1s²2s²2p⁶3s¹3p¹

E

Which of the following lists the substances F₂, HCL and HF in order of increasing boiling point A. HF < HCl < F2 B. HF < F2 <HCl C. HCl < F2 < HF D. HCl < HF < F2 E. F2 < HCl < HF

E

Which of the following process involves the greatest increase in entropy A. So3 + H2 → SO2 + H2O B. N2 + 3H2 → 2NH3 C. Ag + Cl- →AgCl D. C2H2 + 2H2 → C2H6 E. MgSo3 →MgO + So2

E

Which of the following statements is true for the equilibrium vapor pressure of a liquid in a closed system? A. It remains constant when the temperature increases B. It decreases to half its original value if the volume of the gas phase is doubled C. It increases to twice its original value if the volume of the liquid phase is doubled D. It decreases to half its original value if the surface area of the liquid is reduced by one half E. it is independent of the volume of the vapor phase

E

The reaction in which a single species is both oxidized and reduced

E (2 H2O --> O2 + 2H2O)

The graph above shows the results of a study of the reaction of X with a large excess of Y to yield Z. The concentrations of X and Y were measured over a period of time. According to the results, which of the following can be concluded about the rate law for the reaction under the conditions studied?

It is first order in [X].

X → Products A student studied the kinetics of the reaction represented above by measuring the concentration of the reactant, X, over time. The data are plotted in the graph below. Which of the following procedures will allow the student to determine the rate constant, k , for the reaction?

Plot ln [X] versus time and determine the magnitude of the slope.

The data from a study of the decomposition of NO2(g) to form NO(g) and O2(g) are given in the table above. Which of the following rate laws is consistent with the data?

Rate=k[NO2]2

A sample of N2O5 was placed in an evacuated container, and the reaction represented above occurred. The value of PN2O5, the partial pressure of N2O5(g), was measured during the reaction and recorded in the table below. Which of the following correctly describes the reaction?

The decomposition of N2O5 is a first-order reaction.

2 H2O2(aq) → 2 H2O(l) + O2(g) ΔH° = −196 kJ/molrxn The decomposition of H2O2(aq) is represented by the equation above. A student monitored the decomposition of a 1.0 L sample of H2O2(aq) at a constant temperature of 300. K and recorded the concentration of H2O2 as a function of time. The results are given in the table below. Which of the following statements is a correct interpretation of the data regarding how the order of the reaction can be determined?

The reaction is first order if the plot of ln [H2O2] versus time is a straight line.

Which of the following best identifies the rate constant kk for the reaction based on the information in the plot of ln[H2O2] versus time (t) ?

k=−(slope of plot)

For the reaction represented above at 25 C, what are the sings of delta H, S, G

∆H : - ∆S : - ∆G: -