/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 132 At \(25^{\circ} \mathrm{C}\), th... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

At \(25^{\circ} \mathrm{C}\), the rate constant for the ozone-depleting reaction: $$ \mathrm{O}(g)+\mathrm{O}_{3}(g) \longrightarrow 2 \mathrm{O}_{2}(g) $$ is \(7.9 \times 10^{-15} \mathrm{~cm}^{3} / \mathrm{molecule} \cdot \mathrm{s}\). Express the rate constant in units of \(1 / M \cdot \mathrm{s}\).

Short Answer

Expert verified
The rate constant is \(4.756 \times 10^{12} \; 1/M \cdot \mathrm{s}\).

Step by step solution

01

Understand the Units

The given rate constant is in the units of \(\mathrm{cm}^{3} / \mathrm{molecule} \cdot \mathrm{s}\). We need to convert it to \(1 / M \cdot \mathrm{s}\), where \(M\) stands for molarity (moles per liter).To achieve this, we require the conversion between molecules and moles using Avogadro's number, \(N_A = 6.022 \times 10^{23} \; \mathrm{molecules/mol}\).We also need to convert cubic centimeters to liters (where \(1 \; \mathrm{L} = 10^3 \; \mathrm{cm}^3\)).
02

Conversion from Cubic Centimeters to Liters

Convert \(\mathrm{cm}^3\) to liters for the volume component of the rate constant.Since \(1 \; \mathrm{L} = 10^3 \; \mathrm{cm}^3\),do the following transformation:\[7.9 \times 10^{-15} \; \mathrm{cm}^{3} / \mathrm{molecule} \cdot \mathrm{s} = 7.9 \times 10^{-15} \times 10^3 \; \mathrm{L} / \mathrm{molecule} \cdot \mathrm{s}.\]This results in:\(7.9 \times 10^{-12} \; \mathrm{L} / \mathrm{molecule} \cdot \mathrm{s}\).
03

Use Avogadro's Number to Convert Molecules to Moles

Next, convert molecules to moles:The mole conversion involves substituting \(\mathrm{molecule}^{-1}\) with \(\mathrm{mol}^{-1}\) using Avogadro's number\(N_A = 6.022 \times 10^{23} \; \mathrm{molecules/mol}\).Use the transformation:\[(7.9 \times 10^{-12} \; \mathrm{L} / \mathrm{molecule} \cdot \mathrm{s}) \times 6.022 \times 10^{23} \; \mathrm{molecules/mol}.\]This yields:\[7.9 \times 10^{-12} \times 6.022 \times 10^{23} \; \mathrm{L} / \mathrm{mol} \cdot \mathrm{s} = 4.756 \times 10^{12} \; \mathrm{L} / \mathrm{mol} \cdot \mathrm{s}.\]
04

Express in Molarity Units

The result from Step 3,\(4.756 \times 10^{12} \; \mathrm{L/mol} \cdot \mathrm{s}\),is equivalent to\( 4.756 \times 10^{12} \; 1/M \cdot \mathrm{s}\),since 1 M = 1 mole/liter.Thus, the final value in desired units is:\(\boxed{4.756 \times 10^{12} \; 1/M \cdot \mathrm{s}}.\)

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Ozone-Depleting Reaction
Ozone-depleting reactions are chemical processes that reduce the concentration of ozone in the Earth's stratosphere. One important reaction involves atomic oxygen (\(\text{O}\)) reacting with ozone (\(\text{O}_3\)) to produce oxygen gas (\(\text{O}_2\)). This reaction contributes to the thinning of the ozone layer, which protects the planet from harmful ultraviolet radiation. Understanding the rate constant of such reactions is essential to assess their impact on atmospheric chemistry. By converting the units of the rate constant, scientists can better relate these values to conditions useful in environmental studies.
Avogadro's Number
Avogadro's number is a fundamental constant in chemistry, defined as the number of atoms, ions, or molecules in one mole of a substance. Its value is approximately \(6.022 \times 10^{23}\). This large number allows chemists to count particles at the microscopic level by relating them to a quantity, the mole, which is easier to work with in the lab and calculations.
When converting units from molecules to moles, Avogadro's number is crucial. In this problem, it transforms the rate constant from per molecule to per mole, allowing the rate to be expressed in terms of molarity, which is standard in chemical kinetics.
Molarity
Molarity represents the concentration of a solute in a solution. It's expressed in moles of solute per liter of solution \((M =\text{mol/L})\).
Molarity is an important concept because it provides a simple way to express concentration that is widely applicable in chemical reactions. In this exercise, converting the rate constant to units involving molarity makes it more accessible for use in lab experiments and calculations. This unit conversion allows scientists to predict how fast reactions occur under different conditions in a way that is relatable to experimental setups.
Unit Conversion
Unit conversion involves changing a measurement from one set of units to another. It is essential in science to ensure that values can be easily compared and used in different contexts.
For this problem, the conversion from \(\text{cm}^3/\text{molecule}\cdot\text{s} \) to \(1/M\cdot\text{s}\) requires two main steps:
  • Converting cubic centimeters to liters using the relation \(1 \text{ L} = 1000 \text{ cm}^3\).
  • Using Avogadro's number to transition from molecules to moles.
By doing these conversions, we effectively translate the rate constant into a format that aligns with standard chemical practices, enhancing its interpretability and utility in experiments.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

The integrated rate law for the zeroth-order reaction \(\mathrm{A} \longrightarrow \mathrm{B}\) is \([\mathrm{A}]_{t}=[\mathrm{A}]_{0}-k t .\) (a) Sketch the following plots: (i) rate versus \([\mathrm{A}]_{t}\) and (ii) \([\mathrm{A}]_{t}\) versus \(t\). (b) Derive an expression for the half-life of the reaction. (c) Calculate the time in half-lives when the integrated rate law is \(n o\) longer valid, that is, when \([\mathrm{A}]_{t}=0\).

Ethanol is a toxic substance that, when consumed in excess, can impair respiratory and cardiac functions by interference with the neurotransmitters of the nervous system. In the human body, ethanol is metabolized by the enzyme alcohol dehydrogenase to acetaldehyde, which causes hangovers. Based on your knowledge of enzyme kinetics, explain why binge drinking (i.e., consuming too much alcohol too fast) can prove fatal.

Explain why most metals used in catalysis are transition metals.

A protein molecule \(\mathrm{P}\) of molar mass \(\mathscr{M}\) dimerizes when it is allowed to stand in solution at room temperature. A plausible mechanism is that the protein molecule is first denatured (i.e., loses its activity due to a change in overall structure) before it dimerizes: \(\mathrm{P} \stackrel{k}{\longrightarrow} \mathrm{P}^{*}(\) denatured \() \quad\) (slow) $$ 2 \mathrm{P}^{*} \longrightarrow \mathrm{P}_{2} $$ (fast) where the asterisk denotes a denatured protein molecule. Derive an expression for the average molar mass (of \(\mathrm{P}\) and \(\left.\mathrm{P}_{2}\right), \bar{U},\) in terms of the initial protein concentration \([\mathrm{P}]_{0}\) and the concentration at time \(t,[\mathrm{P}]_{t},\) and \(\mathscr{M} .\) Describe how you would determine \(k\) from molar mass measurements.

The rate law for the reaction: $$ \mathrm{NH}_{4}^{+}(a q)+\mathrm{NO}_{2}^{-}(a q) \longrightarrow \mathrm{N}_{2}(g)+2 \mathrm{H}_{2} \mathrm{O}(l) $$ is given by rate \(=k\left[\mathrm{NH}_{4}^{+}\right]\left[\mathrm{NO}_{2}^{-}\right]\). At \(25^{\circ} \mathrm{C},\) the rate constant is \(3.0 \times 10^{-4} / M \cdot \mathrm{s} .\) Calculate the rate of the reaction at this temperature if \(\left[\mathrm{NH}_{4}^{+}\right]=0.36 M\) and \(\left[\mathrm{NO}_{2}^{-}\right]=0.075 \mathrm{M}\).

See all solutions

Recommended explanations on Chemistry Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.