Campbell Biology in Focus
Campbell Biology in Focus
3rd Edition
ISBN: 9780134710679
Author: Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Rebecca Orr
Publisher: PEARSON
bartleby

Videos

Textbook Question
Book Icon
Chapter 2, Problem 1TYU

The reactivity of an atom arises from

  1. A.    the average distance of the outermost electron shell from the nucleus.
  2. B.     the existence of unpaired electrons in the valence shell.
  3. C.     the sum of the potential energies of all the electron shells.
  4. D.    the potential energy of the valence shall.
Expert Solution & Answer
Check Mark
Summary Introduction

Introduction:

An atom is the smallest possible particle of an element. It is the basic unit of any structure found in the universe. Two or more atoms together make a molecule.

Answer to Problem 1TYU

Correct answer:

The reactivity of an atom arises from the existence of unpaired electrons in the valence shell.

Therefore, option (B) is correct.

Explanation of Solution

Reason for the correct statement:

Unpaired electrons in a valence shell are unstable in nature and in order to become stable, an atom can lose or gain electrons and becomes reactive.

Option (B) is given as “the existence of unpaired electrons in the valence shell”.

As “the reactivity of an atom arises from the existence of unpaired electrons in the valence shell”, it is the right answer.

Hence, option (B) is correct.

Reasons for the incorrect statements:

Option (A) is given as “the average distance of the outermost electron shell from the nucleus”.

If the distance of the outermost electron shell is large, then there would be a lesser nuclear effective charge. Thus, an electron can easily be expelled out of its shell. Thus, it does not cause an atomic reactivity. Hence, it is the wrong answer.

Option (C) is given as “the sum of the potential energies of all the electron shells”.

The sum of the potential energies of all the electron shells affects only the chemical properties of the atom and is not involved in its reactivity. Hence, it is the wrong answer.

Option (D) is given as “the potential energies of the valence shell”.

The potential energy of the valence shell decides which shell would get the electron first and is not involved in its reactivity. Hence, it is the wrong answer.

Hence, options (A), (C), and (D) are incorrect.

Conclusion

The number of electrons present in the outermost shell of an atom determines the atom reactivity.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
The diagram below illustrates a quorum sensing pathway from Staphylococcus aureus. Please answer the following questions. 1. Autoinduction is part of the quorum sensing system. Which promoter (P2 or P3) is critical for autoinduction? 2)This staphylococcus aureus grows on human wounds, causing severe infections. You would like to start a clinical trial to treat these wound infections. Please describe: a) What molecule do you recommend for the trial. Why? b) Your trial requires that Staphylococcus aureus be isolated from the wound and submitted to genome sequencing before admittance. Why? What are you testing for?  3) If a mutation arises where the Promoter P3 is constitutively active, how would that influence sensitivity to AIP? Please explain your rationale. 4) This pathway is sensitive to bacterial cell density. Describe two separate mutation that would render the pathway active independent of cell density. Briefly explain your rationale. Mutation 1 Mutation 2
There is currently a H5N1 cattle outbreak in North America. According to the CDC on Feb 26*: "A multistate outbreak of HPAI A(H5N1) bird flu in dairy cows was first reported on March 25, 2024. This is the first time that these bird flu viruses had been found in cows. In the United States, since 2022, USDA has reported HPAI A(H5N1) virus detections in more than 200 mammals." List and describe two mechanisms that could lead to this H5N1 influenza strain evolving to spread in human:  Mechanisms 1: Mechanisms 2: For the mutations to results in a human epidered they would need to change how the virus interacts with the human host. In the case of mutations that may promote an epidemic, provide an example for: a protein that might incur a mutation: how the mutation would change interactions with cells in the respiratory tract (name the receptor on human cells) List two phenotypic consequence from this mutation that would increase human risk
You have a bacterial strain with the CMU operon: a) As shown in the image below, the cmu operon encodes a peptide (Pep1), as well as a kinase and regulator corresponding to a two-component system. The cmu operon is activated when Pep 1 is added to the growth media. Pep1 is a peptide that when added extracellularly leads to activation of the Cmu operon. Pep1 cmu-kinase cmu-regulator You also have these genetic components in other strains: b) An alternative sigma factor, with a promoter activated by the cmu-regulator, that control a series of multiple operons that together encode a transformasome (cellular machinery for transformation). c) the gene cl (a repressor). d) the promoter X, which includes a cl binding site (and in the absence of cl is active). e) the gene gp (encoding a green fluorescence protein). Using the cmu operon as a starting point, and assuming you can perform cloning to rearrange any of these genomic features, how would you use one or more of these to modify the…

Chapter 2 Solutions

Campbell Biology in Focus

Knowledge Booster
Background pattern image
Biology
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
Concepts of Biology
Biology
ISBN:9781938168116
Author:Samantha Fowler, Rebecca Roush, James Wise
Publisher:OpenStax College
Text book image
Biology Today and Tomorrow without Physiology (Mi...
Biology
ISBN:9781305117396
Author:Cecie Starr, Christine Evers, Lisa Starr
Publisher:Cengage Learning
Text book image
Anatomy & Physiology
Biology
ISBN:9781938168130
Author:Kelly A. Young, James A. Wise, Peter DeSaix, Dean H. Kruse, Brandon Poe, Eddie Johnson, Jody E. Johnson, Oksana Korol, J. Gordon Betts, Mark Womble
Publisher:OpenStax College
Text book image
BIOLOGY:CONCEPTS+APPL.(LOOSELEAF)
Biology
ISBN:9781305967359
Author:STARR
Publisher:CENGAGE L
Text book image
Biology: The Unity and Diversity of Life (MindTap...
Biology
ISBN:9781337408332
Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa Starr
Publisher:Cengage Learning
Text book image
Body Structures & Functions Updated
Biology
ISBN:9780357191606
Author:Scott
Publisher:Cengage
GCSE Chemistry - Acids and Bases #34; Author: Cognito;https://www.youtube.com/watch?v=vt8fB3MFzLk;License: Standard youtube license