Question 1

The reaction that occurs in a Breathalyzer, a device used to determine the alcohol level in a person's bloodstream, is given below. If the rate of appearance of Cr₂(SO₄)₃ is 1.64 mol min^-1 at a particular moment, what is the rate of disappearance of C₂H₆O at that moment? 2K₂Cr₂O₇ + 8H₂SO₄ + 3C₂H₆O → 2Cr₂(SO₄)₃ + 2K₂SO₄ + 11H₂O

Accepted Answer

The answer of The reaction that occurs in a Breathalyzer,...

Question 2

The combustion of ethylene proceeds by the reaction C₂H₄(g)+ 3O₂(g)→ 2CO₂(g)+ 2H₂O(g) When the rate of disappearance of O₂ is 0.23 mol L^-1 s^-1, the rate of disappearance of C₂H₄ is ________ mol L^-1 s^-1.

Accepted Answer

From the balanced equation, the stoichiometry between the reactants and products is 1:3. Therefore, the rate of disappearance of C2H4 is three times the rate of disappearance of O2, which gives:

rate(C2H4) = 3 x 0.23 mol L^-1 s^-1 = 0.69 mol L^-1 s^-1

Therefore, the answer is (B) 0.077.

Question 3

The combustion of ethylene proceeds by the reaction C₂H₄(g)+ 3O₂(g)→ 2CO₂(g)+ 2H₂O(g) When the rate of disappearance of O₂ is 0.28 mol L^-1 s^-1, the rate of appearance of CO₂ is ________ Mol L^-1 s^-1.

Accepted Answer

From the stoichiometry of the reaction, we can see that 3 moles of O2 are consumed for every 2 moles of CO2 produced. Therefore, the rate of appearance of CO2 is 2/3 times the rate of disappearance of O2. Thus, the rate of appearance of CO2 is 2/3 * 0.28 mol L-1 s-1 = 0.19 mol L-1 s-1.

Question 4

The isomerization of methylisonitrile to acetonitrile CH₃NC(g)→ CH₃CN(g) Is first order in CH₃NC. The rate constant for the reaction is 9.45 × 10^-5 s^-1 at 478 K. The half-life of the reaction when the initial [CH₃NC] is 0.030 mol L^-1 is ________ s.

Accepted Answer

The answer of The isomerization of methylisonitrile to acetonitrile CH₃NC(g)→...

Question 5

For a particular first-order reaction, it takes 24 minutes for the concentration of the reactant to decrease to 25% of its initial value. What is the value for rate constant (in s^-1)for the reaction?

Accepted Answer

The answer of For a particular first-order reaction, it takes...

Question 6

The rate of disappearance of HBr in the gas phase reaction 2HBr(g)→ H₂(g)+ Br₂(g) Is 0.301 mol L^-1 s^-1 at 150 °C. The rate of appearance of Br₂ is ________ mol L^-1 s^-1.

Accepted Answer

The answer of The rate of disappearance of HBr in...

Question 7

The elementary reaction 2NO₂(g)→ 2NO(g)+ O₂(g) Is second order in NO₂ and the rate constant at 501 K is 7.93 × 10^-3 L mol^-1 s^-1. The reaction half-life at this temperature when [NO₂]₀ = 0.45 mol L^-1 is ________ s.

Accepted Answer

The answer of The elementary reaction 2NO₂(g)→ 2NO(g)+ O₂(g) Is second...

Question 8

The first-order reaction, 2N₂O(g)→ 2N₂(g)+ O₂(g), has a rate constant equal to 0.76 s^-1 at 1000 K. How long will it take for the concentration of N₂O to decrease to 12% of its initial concentration?

Accepted Answer

The reaction is a first-order reaction, so we can use the integrated rate law for a first-order reaction: ln([N₂O]/[N₂O]0) = -kt where [N₂O] is the concentration at time t, [N₂O]0 is the initial concentration, k is the rate constant, and t is time. We want to find the time it takes for [N₂O] to decrease to 12% of its initial concentration, so we can set [N₂O]/[N₂O]0 equal to 0.12: ln(0.12) = -0.76t Solving for t: t = -ln(0.12)/0.76 ≈ 2.8 s

Question 9

The isomerization reaction, CH₃NC → CH₃CN, is first order and the rate constant is equal to 0.46 s^-1 at 600 K. What is the concentration of CH₃NC after 0.20 minutes if the initial concentration is 0.30 mol L^-1?

Accepted Answer

The integrated rate law for a first-order reaction is:ln[A]t = -kt + ln[A]0where [A]t is the concentration of the reactant at time t, k is the rate constant, and [A]0 is the initial concentration of the reactant.We can use this equation to calculate the concentration of CH3NC after 0.20 minutes:ln[CH3NC]t = -0.46 s-1 * (0.20 min * 60 s/min) + ln(0.30 mol L-1)ln[CH3NC]t = -5.52[CH3NC]t = 2.7 × 10-3 mol L-1

Question 10

Carbon-14, which is present in all living tissue, radioactively decays via a first-order process. A one-gram sample of wood taken from a living tree gives a rate for carbon-14 decay of 13.6 counts per minute. If the half-life for carbon-14 is 5720 years, how old is a wood sample that gives a rate for carbon-14 decay of 11.9 counts per minute?

Accepted Answer

The answer of Carbon-14, which is present in all living...

Question 11

The first-order reaction, SO₂Cl₂ → SO₂ + Cl₂, has a rate constant equal to 2.20 × 10^-5 s^-1 at 593 K. What percentage of the initial amount of SO₂Cl₂ will remain after 6.00 hours?

Accepted Answer

The answer of The first-order reaction, SO₂Cl₂ → SO₂ +...

Question 12

The rate constant, k, for a first-order reaction is equal to 4.2 × 10^-4 s^-1. What is the half-life for the reaction?

Accepted Answer

The half-life for a first-order reaction can be calculated using the equation: t1/2 = ln(2)/k Plugging in the given value for k, we get: t1/2 = ln(2)/4.2 × 10^-4 s^-1 Simplifying this expression gives: t1/2 = 1.7 × 10³ s Therefore, the correct answer is choice C.

Question 13

For the first-order reaction, 2N₂O(g)→ 2N₂(g)+ O₂(g), what is the concentration of N₂O after 3 half-lives if 0.25 mol of N₂O is initially placed into a 1.00 L reaction vessel?

Accepted Answer

The answer of For the first-order reaction, 2N₂O(g)→ 2N₂(g)+ O₂(g),...

Question 14

The first-order reaction, SO₂Cl₂ → SO₂ + Cl₂, has a half-life of 8.75 hours at 593 K. How long will it take for the concentration of SO₂Cl₂ to fall to 16.5% of its initial value?

Accepted Answer

For a first-order reaction, the time $ t $ required for the concentration of a reactant to fall to a fraction $ f $ of its initial value is given by the formula $ t = \frac{\ln(1/f)}{k} $, where $ k $ is the rate constant. The half-life ($ t_{1/2} $) of a first-order reaction is related to the rate constant by $ t_{1/2} = \frac{\ln(2)}{k} $. Given that the half-life is 8.75 hours, we can find $ k $ and then calculate $ t $ for the concentration to fall to 16.5% (or 0.165) of its initial value.1. Calculate the rate constant $ k $ using the half-life formula:$$ k = \frac{\ln(2)}{t_{1/2}} = \frac{\ln(2)}{8.75} $$2. Calculate the time $ t $ for the concentration to fall to 16.5% of its initial value:$$ t = \frac{\ln(1/0.165)}{k} = \frac{\ln(1/0.165)}{\ln(2)/8.75} $$This calculation will give $ t $ as approximately 22.7 hours, which means it takes 22.7 hours for the concentration to fall to 16.5% of its initial value.

Question 15

The rate of disappearance of HBr in the gas phase reaction 2HBr(g)→ H₂ (g)+ Br₂ (g) Is 0.130 mol L^-1 s^-1 at 150 °C. The rate of reaction is ________ mol L^-1 s^-1.

Accepted Answer

The balanced equation for the reaction is:
2 HBr(g) → H2(g) + Br2(g)

The rate of disappearance of HBr is given as 0.130 mol L-1 s-1, which means that the rate of the reaction is half of that, since 2 mol of HBr is consumed in the reaction.
Rate of reaction = 0.130/2 = 0.0650 mol L-1 s-1
Therefore, the answer is B.

Question 16

The isomerization of methylisonitrile to acetonitrile CH₃NC(g)→ CH₃CN(g) Is first order in CH₃NC. The half-life of the reaction is 5.20 × 10¹ s at 545 K. The rate constant when the initial [CH₃NC] is 0.030 mol L^-1 is ________ s^-1.

Accepted Answer

For a first-order reaction, the rate constant k can be calculated using the formula k = 0.693 / t₁/₂. Given the half-life t₁/₂ = 5.20 × 10¹ s, k = 0.693 / (5.20 × 10¹ s) = 0.0133 s⁻¹.

Question 17

What is the overall reaction order for the reaction that has the rate law Rate = k[NO₂][O]?

Accepted Answer

The answer of What is the overall reaction order for...

Question 18

SO₂Cl₂ decomposes in the gas phase by the reaction SO₂Cl₂(g)→ SO₂(g)+ Cl₂(g) The reaction is first order in SO₂Cl₂ and the rate constant is 3.0 × 10^-⁶ s^-1at 600 K. A vessel is charged with 2.4 atm of SO₂Cl₂ at 600 K. The partial pressure of SO₂Cl₂ at 3.0 × 10⁵ is ________ atm.

Accepted Answer

We can use the first-order rate law equation to solve for the partial pressure of SO₂Cl₂ after a certain amount of time has passed: ln(P0/P) = kt where P0 is the initial partial pressure of SO₂Cl₂, P is the partial pressure at a time t, k is the rate constant, and ln denotes the natural logarithm. We can rearrange this equation to solve for P: P = P0 * e^(-kt) Plugging in the given values, we get: P = 2.4 atm * e^(-(3.0 × 10^15 s^-1) * (5.0 min * 60 s/min)) P = 0.978 atm Rounding to two significant figures, the answer is 0.98 atm (choice C).

Question 19

The decomposition of N₂O₅ in solution in carbon tetrachloride proceeds via the reaction 2N₂O₅(soln)→ 4NO₂(soln)+ O₂(soln) The reaction is first order and has a rate constant of 4.82 × 10^-3 s^-1 at 64 °C. If the reaction is initiated with 0.058 mol in a 1.00 L vessel, how many moles remain after 151 s?

Accepted Answer

We will use the integrated rate law for a first-order reaction, which is:

ln([A]/[A]0) = -kt

Where [A] is the concentration of the reactant at a given time, [A]0 is the initial concentration, k is the rate constant, and t is time.

Substituting the given values, we get:

ln([A]/0.058) = -4.82 × 10^-3 × 151

Solving for [A], we get:

[A] = 0.028 mol/L

Therefore, the number of moles remaining after 151 s is 0.028 mol (Option C).

Question 20

The following reaction is first order, C₂H₆ → 2CH₃. If the rate constant is equal to 5.5 × 10^-4 s^-1 at 1000 K, how long will it take for 0.35 mol of C₂H₆ in a 1.00 L container to decrease to 0.20 mol in the same container?

Accepted Answer

The answer of The following reaction is first order, C₂H₆...

Quiz 13: Chemical Kinetics

The combustion of ethylene proceeds by the reaction C₂H₄(g) + 3O₂(g) → 2CO₂(g) + 2H₂O(g) When the rate of disappearance of O₂ is 0.23 mol L^-1 s^-1, the rate of disappearance of C₂H₄ is ________ mol L^-1 s^-1.

The combustion of ethylene proceeds by the reaction C₂H₄(g) + 3O₂(g) → 2CO₂(g) + 2H₂O(g) When the rate of disappearance of O₂ is 0.28 mol L^-1 s^-1, the rate of appearance of CO₂ is ________ Mol L^-1 s^-1.

The isomerization of methylisonitrile to acetonitrile CH₃NC(g) → CH₃CN(g) Is first order in CH₃NC. The rate constant for the reaction is 9.45 × 10^-5 s^-1 at 478 K. The half-life of the reaction when the initial [CH₃NC] is 0.030 mol L^-1 is ________ s.

For a particular first-order reaction, it takes 24 minutes for the concentration of the reactant to decrease to 25% of its initial value. What is the value for rate constant (in s^-1) for the reaction?

The rate of disappearance of HBr in the gas phase reaction 2HBr(g) → H₂(g) + Br₂(g) Is 0.301 mol L^-1 s^-1 at 150 °C. The rate of appearance of Br₂ is ________ mol L^-1 s^-1.

The elementary reaction 2NO₂(g) → 2NO(g) + O₂(g) Is second order in NO₂ and the rate constant at 501 K is 7.93 × 10^-3 L mol^-1 s^-1. The reaction half-life at this temperature when [NO₂]₀ = 0.45 mol L^-1 is ________ s.

The first-order reaction, 2N₂O(g) → 2N₂(g) + O₂(g) , has a rate constant equal to 0.76 s^-1 at 1000 K. How long will it take for the concentration of N₂O to decrease to 12% of its initial concentration?

The isomerization reaction, CH₃NC → CH₃CN, is first order and the rate constant is equal to 0.46 s^-1 at 600 K. What is the concentration of CH₃NC after 0.20 minutes if the initial concentration is 0.30 mol L^-1?

The first-order reaction, SO₂Cl₂ → SO₂ + Cl₂, has a rate constant equal to 2.20 × 10^-5 s^-1 at 593 K. What percentage of the initial amount of SO₂Cl₂ will remain after 6.00 hours?

The rate constant, k, for a first-order reaction is equal to 4.2 × 10^-4 s^-1. What is the half-life for the reaction?

For the first-order reaction, 2N₂O(g) → 2N₂(g) + O₂(g) , what is the concentration of N₂O after 3 half-lives if 0.25 mol of N₂O is initially placed into a 1.00 L reaction vessel?

The first-order reaction, SO₂Cl₂ → SO₂ + Cl₂, has a half-life of 8.75 hours at 593 K. How long will it take for the concentration of SO₂Cl₂ to fall to 16.5% of its initial value?

The rate of disappearance of HBr in the gas phase reaction 2HBr(g) → H₂ (g) + Br₂ (g) Is 0.130 mol L^-1 s^-1 at 150 °C. The rate of reaction is ________ mol L^-1 s^-1.

The isomerization of methylisonitrile to acetonitrile CH₃NC(g) → CH₃CN(g) Is first order in CH₃NC. The half-life of the reaction is 5.20 × 10¹ s at 545 K. The rate constant when the initial [CH₃NC] is 0.030 mol L^-1 is ________ s^-1.

What is the overall reaction order for the reaction that has the rate law Rate = k[NO₂][O]?

The following reaction is first order, C₂H₆ → 2CH₃. If the rate constant is equal to 5.5 × 10^-4 s^-1 at 1000 K, how long will it take for 0.35 mol of C₂H₆ in a 1.00 L container to decrease to 0.20 mol in the same container?

Quiz 13: Chemical Kinetics

The combustion of ethylene proceeds by the reaction C2H4(g) + 3O2(g) → 2CO2(g) + 2H2O(g) When the rate of disappearance of O2 is 0.23 mol L-1 s-1, the rate of disappearance of C2H4 is ________ mol L-1 s-1.

The combustion of ethylene proceeds by the reaction C2H4(g) + 3O2(g) → 2CO2(g) + 2H2O(g) When the rate of disappearance of O2 is 0.28 mol L-1 s-1, the rate of appearance of CO2 is ________ Mol L-1 s-1.

The isomerization of methylisonitrile to acetonitrile CH3NC(g) → CH3CN(g) Is first order in CH3NC. The rate constant for the reaction is 9.45 × 10-5 s-1 at 478 K. The half-life of the reaction when the initial [CH3NC] is 0.030 mol L-1 is ________ s.

For a particular first-order reaction, it takes 24 minutes for the concentration of the reactant to decrease to 25% of its initial value. What is the value for rate constant (in s-1) for the reaction?

The rate of disappearance of HBr in the gas phase reaction 2HBr(g) → H2(g) + Br2(g) Is 0.301 mol L-1 s-1 at 150 °C. The rate of appearance of Br2 is ________ mol L-1 s-1.

The elementary reaction 2NO2(g) → 2NO(g) + O2(g) Is second order in NO2 and the rate constant at 501 K is 7.93 × 10-3 L mol-1 s-1. The reaction half-life at this temperature when [NO2]0 = 0.45 mol L-1 is ________ s.

The first-order reaction, 2N2O(g) → 2N2(g) + O2(g) , has a rate constant equal to 0.76 s-1 at 1000 K. How long will it take for the concentration of N2O to decrease to 12% of its initial concentration?

The isomerization reaction, CH3NC → CH3CN, is first order and the rate constant is equal to 0.46 s-1 at 600 K. What is the concentration of CH3NC after 0.20 minutes if the initial concentration is 0.30 mol L-1?

The first-order reaction, SO2Cl2 → SO2 + Cl2, has a rate constant equal to 2.20 × 10-5 s-1 at 593 K. What percentage of the initial amount of SO2Cl2 will remain after 6.00 hours?

The rate constant, k, for a first-order reaction is equal to 4.2 × 10-4 s-1. What is the half-life for the reaction?

For the first-order reaction, 2N2O(g) → 2N2(g) + O2(g) , what is the concentration of N2O after 3 half-lives if 0.25 mol of N2O is initially placed into a 1.00 L reaction vessel?

The first-order reaction, SO2Cl2 → SO2 + Cl2, has a half-life of 8.75 hours at 593 K. How long will it take for the concentration of SO2Cl2 to fall to 16.5% of its initial value?

The rate of disappearance of HBr in the gas phase reaction 2HBr(g) → H2 (g) + Br2 (g) Is 0.130 mol L-1 s-1 at 150 °C. The rate of reaction is ________ mol L-1 s-1.

The isomerization of methylisonitrile to acetonitrile CH3NC(g) → CH3CN(g) Is first order in CH3NC. The half-life of the reaction is 5.20 × 101 s at 545 K. The rate constant when the initial [CH3NC] is 0.030 mol L-1 is ________ s-1.

What is the overall reaction order for the reaction that has the rate law Rate = k[NO 2][O] ?

SO2Cl2 decomposes in the gas phase by the reaction SO2Cl2(g) → SO2(g) + Cl2(g) The reaction is first order in SO2Cl2 and the rate constant is 3.0 × 10-6 s-1at 600 K. A vessel is charged with 2.4 atm of SO2Cl2 at 600 K. The partial pressure of SO2Cl2 at 3.0 × 105 is ________ atm.

The following reaction is first order, C2H6 → 2CH3. If the rate constant is equal to 5.5 × 10-4 s-1 at 1000 K, how long will it take for 0.35 mol of C2H6 in a 1.00 L container to decrease to 0.20 mol in the same container?

The combustion of ethylene proceeds by the reaction C₂H₄(g) + 3O₂(g) → 2CO₂(g) + 2H₂O(g) When the rate of disappearance of O₂ is 0.23 mol L^-1 s^-1, the rate of disappearance of C₂H₄ is ________ mol L^-1 s^-1.

The combustion of ethylene proceeds by the reaction C₂H₄(g) + 3O₂(g) → 2CO₂(g) + 2H₂O(g) When the rate of disappearance of O₂ is 0.28 mol L^-1 s^-1, the rate of appearance of CO₂ is ________ Mol L^-1 s^-1.

The isomerization of methylisonitrile to acetonitrile CH₃NC(g) → CH₃CN(g) Is first order in CH₃NC. The rate constant for the reaction is 9.45 × 10^-5 s^-1 at 478 K. The half-life of the reaction when the initial [CH₃NC] is 0.030 mol L^-1 is ________ s.

For a particular first-order reaction, it takes 24 minutes for the concentration of the reactant to decrease to 25% of its initial value. What is the value for rate constant (in s^-1) for the reaction?

The rate of disappearance of HBr in the gas phase reaction 2HBr(g) → H₂(g) + Br₂(g) Is 0.301 mol L^-1 s^-1 at 150 °C. The rate of appearance of Br₂ is ________ mol L^-1 s^-1.

The elementary reaction 2NO₂(g) → 2NO(g) + O₂(g) Is second order in NO₂ and the rate constant at 501 K is 7.93 × 10^-3 L mol^-1 s^-1. The reaction half-life at this temperature when [NO₂]₀ = 0.45 mol L^-1 is ________ s.

The first-order reaction, 2N₂O(g) → 2N₂(g) + O₂(g) , has a rate constant equal to 0.76 s^-1 at 1000 K. How long will it take for the concentration of N₂O to decrease to 12% of its initial concentration?

The isomerization reaction, CH₃NC → CH₃CN, is first order and the rate constant is equal to 0.46 s^-1 at 600 K. What is the concentration of CH₃NC after 0.20 minutes if the initial concentration is 0.30 mol L^-1?

The first-order reaction, SO₂Cl₂ → SO₂ + Cl₂, has a rate constant equal to 2.20 × 10^-5 s^-1 at 593 K. What percentage of the initial amount of SO₂Cl₂ will remain after 6.00 hours?

The rate constant, k, for a first-order reaction is equal to 4.2 × 10^-4 s^-1. What is the half-life for the reaction?

For the first-order reaction, 2N₂O(g) → 2N₂(g) + O₂(g) , what is the concentration of N₂O after 3 half-lives if 0.25 mol of N₂O is initially placed into a 1.00 L reaction vessel?

The first-order reaction, SO₂Cl₂ → SO₂ + Cl₂, has a half-life of 8.75 hours at 593 K. How long will it take for the concentration of SO₂Cl₂ to fall to 16.5% of its initial value?

The rate of disappearance of HBr in the gas phase reaction 2HBr(g) → H₂ (g) + Br₂ (g) Is 0.130 mol L^-1 s^-1 at 150 °C. The rate of reaction is ________ mol L^-1 s^-1.

The isomerization of methylisonitrile to acetonitrile CH₃NC(g) → CH₃CN(g) Is first order in CH₃NC. The half-life of the reaction is 5.20 × 10¹ s at 545 K. The rate constant when the initial [CH₃NC] is 0.030 mol L^-1 is ________ s^-1.

What is the overall reaction order for the reaction that has the rate law Rate = k[NO₂][O]?

The following reaction is first order, C₂H₆ → 2CH₃. If the rate constant is equal to 5.5 × 10^-4 s^-1 at 1000 K, how long will it take for 0.35 mol of C₂H₆ in a 1.00 L container to decrease to 0.20 mol in the same container?