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| double arrow symbol chemistry: Quantities, Units and Symbols in Physical Chemistry Christopher M A Brett, Jeremy G Frey, Robert Hinde, Yutaka Kuroda, Roberto Marquardt, Franco Pavese, Martin Quack, Juergen Stohner, Anders J Thor, 2023-11-29 The first IUPAC Manual of Symbols and Terminology for Physicochemical Quantities and Units was published in 1969 with the objective of 'securing clarity and precision, and wider agreement in the use of symbols, by chemists in different countries, among physicists, chemists and engineers, and by editors of scientific journals'. Subsequent revisions have taken account of many developments in the field and were also substantially expanded and improved in presentation in several new editions of what is now widely known as the ‘Green Book of IUPAC’. This abridged version of the forthcoming 4th edition reflects the experience of the contributors and users of the previous editions. The book has been systematically brought up to date and provides a compilation of generally used terms and symbols with brief, understandable definitions and explanations. Tables of important fundamental constants and conversion factors are included. In this abridged guide, the more specialized and complex material has been omitted, retaining, however, the essence of the Green Book. It is particularly intended to be suitable for students and teachers but it should also be useful for scientists, science publishers and organizations working across a multitude of disciplines requiring internationally approved terminology in the area of Physical Chemistry. It now includes the most up to date definitions and constants in agreement with the ‘new SI’ as established by agreement on the International System of Units in Paris in 2019. It should find the widest possible acceptance and use for best practice in science and technology. |
| double arrow symbol chemistry: Basics for Chemistry David A. Ucko, 2013-09-24 Basics of Chemistry provides the tools needed in the study of General Chemistry such as problem solving skills, calculation methods and the language and basic concepts of chemistry. The book is designed to meet the specific needs of underprepared students. Concepts are presented only as they are needed, and developed from the simple to the complex. The text is divided into 18 chapters, each covering some particular aspect of chemistry such as matter, energy, and measurement; the properties of atoms; description of chemical bonding; study of chemical change; and nuclear and organic chemistry. Undergraduate students will find the book as a very valuable academic material. |
| double arrow symbol chemistry: Quantities, Units and Symbols in Physical Chemistry International Union of Pure and Applied Chemistry. Physical and Biophysical Chemistry Division, 2007 Prepared by the IUPAC Physical Chemistry Division this definitive manual, now in its third edition, is designed to improve the exchange of scientific information among the readers in different disciplines and across different nations. This book has been systematically brought up to date and new sections added to reflect the increasing volume of scientific literature and terminology and expressions being used. The Third Edition reflects the experience of the contributors with the previous editions and the comments and feedback have been integrated into this essential resource. This edition has been compiled in machine-readable form and will be available online. |
| double arrow symbol chemistry: Theoretical and physical chemistry Samuel Lawrence Bigelow, 1912 |
| double arrow symbol chemistry: Chemistry for High School , |
| double arrow symbol chemistry: Chemistry John Kenkel, Paul B. Kelter, David S. Hage, 2000-09-21 What a great idea-an introductory chemistry text that connects students to the workplace of practicing chemists and chemical technicians! Tying chemistry fundamentals to the reality of industrial life, Chemistry: An Industry-Based Introduction with CD-ROM covers all the basic principles of chemistry including formulas and names, chemical bon |
| double arrow symbol chemistry: Dictionary of Chemistry , |
| double arrow symbol chemistry: Thought Signs Carl G. Liungman, 1995 The book is the first comprehensive encyclopedia of Western ideograms ever published, unique in its search systems, that allows the reader to locate a symbol by defining just four of its visual characteristics. It is about our graphic cultural heritage as expressed in subway graffiti, fighter jets' signs and emergency exit symbols. It contains 2,300 symbols, 1,600 articles and streamlined reference functions. Ideogram scarved in mammoth teeth by Cro-Magnon men 25,000 years ago, put on modern household appliances by their manufacturers or sprayed on walls by political activists, are all presented in dictionary form for easy reference. Symbols cover current designs used in advertising, logotyping, architecture, design, decoration, religion, politics and astrology. |
| double arrow symbol chemistry: A History of Modern Chemistry Noboru Hirota, 2016 This publication is a translation of the book entitles Gendai Kagakusi (A History of Modern Chemistry) published by Kyoto University Press in 2013. |
| double arrow symbol chemistry: Introduction to Organic Chemistry William H. Brown, Thomas Poon, 2016-01-13 Introduction to Organic Chemistry, 6th Edition provides an introduction to organic chemistry for students who require the fundamentals of organic chemistry as a requirement for their major. It is most suited for a one semester organic chemistry course. In an attempt to highlight the relevance of the material to students, the authors place a strong emphasis on showing the interrelationship between organic chemistry and other areas of science, particularly the biological and health sciences. The text illustrates the use of organic chemistry as a tool in these sciences; it also stresses the organic compounds, both natural and synthetic, that surround us in everyday life: in pharmaceuticals, plastics, fibers, agrochemicals, surface coatings, toiletry preparations and cosmetics, food additives, adhesives, and elastomers. This text is an unbound, three hole punched version. Access to WileyPLUS sold separately. |
| double arrow symbol chemistry: Essentials of Chemistry John Charles Hessler, Albert Lincoln Smith, 1912 |
| double arrow symbol chemistry: Basic Chemistry Concepts and Exercises John Kenkel, 2011-07-08 Chemistry can be a daunting subject for the uninitiated, and all too often, introductory textbooks do little to make students feel at ease with the complex subject matter. Basic Chemistry Concepts and Exercises brings the wisdom of John Kenkel’s more than 35 years of teaching experience to communicate the fundamentals of chemistry in a practical, down-to-earth manner. Using conversational language and logically assembled graphics, the book concisely introduces each topic without overwhelming students with unnecessary detail. Example problems and end-of-chapter questions emphasize repetition of concepts, preparing students to become adept at the basics before they progress to an advanced general chemistry course. Enhanced with visualization techniques such as the first chapter’s mythical microscope, the book clarifies challenging, abstract ideas and stimulates curiosity into what can otherwise be an overwhelming topic. Topics discussed in this reader-friendly text include: Properties and structure of matter Atoms, molecules, and compounds The Periodic Table Atomic weight, formula weights, and moles Gases and solutions Chemical equilibrium Acids, bases, and pH Organic chemicals The appendix contains answers to the homework exercises so students can check their work and receive instant feedback as to whether they have adequately grasped the concepts before moving on to the next section. Designed to help students embrace chemistry not with trepidation, but with confidence, this solid preparatory text forms a firm foundation for more advanced chemistry training. |
| double arrow symbol chemistry: Brown's Introduction to Organic Chemistry William H. Brown, Thomas Poon, 2017-06-28 Introduction to Organic Chemistry, 6th Global Edition provides an introduction to organic chemistry for students who require the fundamentals of organic chemistry as a requirement for their major. It is most suited for a one semester organic chemistry course. In an attempt to highlight the relevance of the material to students, the authors place a strong emphasis on showing the interrelationship between organic chemistry and other areas of science, particularly the biological and health sciences. The text illustrates the use of organic chemistry as a tool in these sciences; it also stresses the organic compounds, both natural and synthetic, that surround us in everyday life: in pharmaceuticals, plastics, fibers, agrochemicals, surface coatings, toiletry preparations and cosmetics, food additives, adhesives, and elastomers. |
| double arrow symbol chemistry: Symmetry (Group Theory) and Mathematical Treatment in Chemistry Takashiro Akitsu, 2018-07-18 The aim of this book Symmetry (Group Theory) and Mathematical Treatment in Chemistry is to be a graduate school-level text about introducing recent research examples associated with symmetry (group theory) and mathematical treatment in inorganic or organic chemistry, physical chemistry or chemical physics, and theoretical chemistry. Chapters contained can be classified into mini-review, tutorial review, or original research chapters of mathematical treatment in chemistry with brief explanation of related mathematical theories. Keywords are symmetry, group theory, crystallography, solid state, topology, molecular structure, electronic state, quantum chemistry, theoretical chemistry, and DFT calculations. |
| double arrow symbol chemistry: Understanding Chemistry Fred M. Dewey, 1994 |
| double arrow symbol chemistry: Inorganic Chemistry Horace Greeley Byers, 1917 |
| double arrow symbol chemistry: Dynamic Combinatorial Chemistry Joost N. H. Reek, Sijbren Otto, 2010-02-02 This long-awaited first book on this exciting new field in organic and supramolecular chemistry explains the fundamentals as well as possible applications of DCC. Authored by the Who's Who of DCC it spans the whole range of topics: catalysts, sensors, polymers, ligands, receptors, concluding with a look at future developments and perspectives. All set to become the standard text in the field, this one-stop reference contains everything organic, catalytic, polymer, physical and biochemists need to know. |
| double arrow symbol chemistry: Dictionary Of Chemistry N. Pradeep Sharma, 1998-09 Chemistry deals with various properties structures and reactions of material substance. Since variety of substances are present in nature and in day to day life, the scope of chemistry is immense. Chemistry has interfaces with all scientific disciplines and a deep understanding of the subject is essential to comprehend its assimilative and distributive properties. The present work is an attempt to present an uptodate, complete and authoritative references for those who wish to maximize their knowledge in the said field. |
| double arrow symbol chemistry: Green Chemistry and the Ten Commandments of Sustainability Stanley E. Manahan, 2011 |
| double arrow symbol chemistry: Chemistry in a Month John Wilkinson, 2003 |
| double arrow symbol chemistry: A Dictionary of Chemistry Richard Rennie, 2016 Covers all aspects of chemistry in over 5,000 entries; includes diagrams, articles, chronologies, and appendices covering the Greek alphabet, the periodic table, and the electromagnetic spectrum. |
| double arrow symbol chemistry: A Dictionary of Chemistry John Daintith, 2008-02-21 Fully revised and updated, the sixth edition of this popular dictionary is the ideal reference resource for students of chemistry, either at school or at university. With over 4,700 entires - over 200 new to this edition - it covers all aspects of chemistry, from physical chemistry to biochemistry. The sixth edition boasts broader coverage in subject areas such as forensics, metallurgy, materials science, and geology, increasing the dictionary's appeal to students in these related fields. There are also biographical entries on key figures, highlighted entries on major topics such as polymers and crystal defects, and a chronology charting the main discoveries in atomic theory, biochemistry, explosives, and plastics. |
| double arrow symbol chemistry: Chemistry for OCR A for Double Award David Lees, John Payne, 2001 This series is for schools following OCR A double or separate award for GCSE science. The resources offer preparation for the OCR exams with teacher support to minimise time spent on administration. The teacher's resources are available on CD-ROM in a fully customizable format. |
| double arrow symbol chemistry: Science in Color Bettina Bock von Wülfingen, 2019-08-19 Color makes its way into natural science images as early as the research process. It serves for self-reflection and for communication within the scientific community. However, color does not follow a standard in the natural sciences: its meaning is contingent, even though culturally conditioned. Digital publishing enhances the use of color in scientific publications; at the same time, globalization promotes the idea of universal color symbolism. This book investigates the function of color in historical and current visualizations for scientific purposes, its epistemic role as a tool, and its long neglect due to symbolic and gender-specific connotations. The publication thus closes a research gap in the natural sciences and the humanities. |
| double arrow symbol chemistry: Electronic Interpretation of Organic Chemistry F. M. Menger, 2013-03-08 Most standard texts in basic organic chemistry require the student to memorize dozens of organic reactions. This is certainly necessary to master the discipline. Unfortunately, most texts do not emphasize why these reactions occur and, just as important, why other reactions that might seem conceivable to the student do not occur. Without this understanding, students tend to forget what they have memorized soon after the course is over. It is the purpose of this book to familiarize the student with the principles governing organic reactivity and to provide a feel for organic chemistry that is impossible to secure by memory alone. Digesting the ideas in this book will, we hope, not only explain the common organic reactions but also allow the student to predict the prod ucts and by-products of reactions he has never seen before. Indeed, the creative student might even become capable of designing new reactions as might be required in a complex organic synthesis. In Chapter 1, we cover the basic principles including bonding, nuclear charge, resonance effects, oxidation-reduction, etc. It is a brief discussion, but it nonetheless provides the basis for understanding reaction mechanisms th~t will be treated later on. We highly recommend that this material be reviewed and that the v VI PREFACE problems be worked at the end of the chapter. Answers are given to all problems. In Chapter 2, reaction mechanisms are presented in an increas ing order of difficulty. |
| double arrow symbol chemistry: Access to Chemistry Avril Higton, Mike Clemmet, Elaine Golding, Alan V Jones, 2007-10-31 This text has been specifically designed to prepare people with previously limited chemical knowledge for entrance into science related courses (such as Foundation and Access courses) which involve chemistry, in higher education. Until now there have been no texts available for use on these courses and this book fills that gap. Access to Chemistry effectively forms a self-study course, which is split into separate modules and units covering the full spread of concepts required for those needing a basic knowledge of chemistry. The material is presented in a friendly and easy-to-use manner which allows the student to pace their acquisition of knowledge and gain increasing confidence in order to succeed in understanding essential relevant concepts. Other useful features of this book include starter diagnostic tests, worked examples and self study tests (with answers) at the end of each unit. In addition to Access or Foundation course students and their tutors, to whom this book will prove essential, it will have an appeal also as a revision text for those needing a 'refresher' after a break in the subject. In addition, it will be of interest to members of the general public who wish to better educate themselves on chemical matters, as it provides a clear and useful insight into areas such as health, home chemicals, business market trends and gardening. |
| double arrow symbol chemistry: Drug Design and Action Joaquín M. Campos Rosa, 2023-12-18 A slow and consistent study of the approaches for drug design can help the foundation for a good scientific intuition. This edition includes over 30 new illustrations, numerous new mechanistic schemes and enhanced original figures. In addition, the use of color makes its study more pleasant and impressive. The Second Edition has been thoroughly revised with a modern look. The chapters on QSAR and Drug Metabolism have been extended, emphasizing concepts, such as the hyperconjugative effect or the anomeric effect, in which the student normally finds it difficult to understand. Stereoelectronic effects are essential to explain the mechanism of action of drugs and therefore, its agile and intuitive handling will allow the student access to both chemical and biological mechanisms, in a more rational way. The text is illustrated with hundreds of formulas and many tables that facilitate the understanding of this interesting discipline, which is halfway between Organic Chemistry, Biochemistry and Pharmacology. This Volume is aimed at building basis principles on drug design and it is likely to be of interest to students reading, pharmacy, pharmacology, and pharmaceutical chemistry. This book emphasizes general principles of drug design and drug action from an organic chemical perspective, rather than from the overview of specific classes of drugs, allowing the reader to extrapolate information to many related classes of drug molecules. This volume presents an organic chemistry’s perspective of how drug are designed and assuming no prior knowledge of biochemistry, and pharmacology. It is written in an informal, clear style so that undergraduates can easily understand the concepts presented. |
| double arrow symbol chemistry: Dictionary of Symbols Carl G. Liungman, 1991 This is a dictionary of graphic symbols, unique in that the symbols may be accessed by identifying four visible characteristics, with an introduction discussing the function of graphic symbols, their cultural history, and more. |
| double arrow symbol chemistry: The Pearson CSAT Manual 2012 Edgar Thorpe, 2012 |
| double arrow symbol chemistry: AP Chemistry Premium, 2024: 6 Practice Tests + Comprehensive Review + Online Practice Neil D. Jespersen, Pamela Kerrigan, 2023-07-04 For more than 80 years, BARRON's has been helping students achieve their goals. Prep for the AP® Chemistry exam with trusted review from our experts. |
| double arrow symbol chemistry: Mathematics for Physical Chemistry Robert G. Mortimer, S.M. Blinder, 2023-02-20 Mathematics for Physical Chemistry, Fifth Edition includes exercises that enable readers to test their understanding and put theory into practice. Chapters are constructed around a sequence of mathematical topics, progressing gradually into more advanced material, before discussing key mathematical skills, including the analysis of experimental data and—new to this edition—complex variables. Includes additional new content on Mathematica and its advanced applications. Drawing on the experience of its expert authors, this book is the ideal supplementary text for practicing chemists and students wanting to sharpen their mathematics skills and understanding of key mathematical concepts for applications across physical chemistry. - Includes updated coverage of key topics, including a review of general algebra and an introduction to group theory - Features previews, objectives, and numerous examples and problems throughout the text to aid learning - Provides chemistry-specific instruction without the distraction of abstract concepts or theoretical issues in pure mathematics - Includes new chapters on complex variables and Mathematica for advanced applications |
| double arrow symbol chemistry: AP Chemistry Premium, 2022-2023: 6 Practice Tests + Comprehensive Content Review + Online Practice Neil D. Jespersen, Pamela Kerrigan, 2021-07-06 A guide to taking the Advanced Placement exam in chemistry, featuring a review of major chemistry concepts, practice and diagnostic tests, test-taking strategies, an overview of the test, and practice problems. |
| double arrow symbol chemistry: General Chemistry Workbook Daniel C. Tofan, 2010-07-28 This workbook is a comprehensive collection of solved exercises and problems typical to AP, introductory, and general chemistry courses, as well as blank worksheets containing further practice problems and questions. It contains a total of 197 learning objectives, grouped in 28 lessons, and covering the vast majority of the types of problems that a student will encounter in a typical one-year chemistry course. It also contains a fully solved, 50-question practice test, which gives students a good idea of what they might expect on an actual final exam covering the entire material. |
| double arrow symbol chemistry: Organic Chemistry Tadashi Okuyama, Howard Maskill, 2013-11 Organic Chemistry: A mechanistic approach combines a focus on core topics and themes with a mechanistic approach to the explanation of the reactions it describes, making it ideal for those looking for a solid understanding of the central themes of organic chemistry. |
| double arrow symbol chemistry: Advances in Quantum Chemistry John R. Sabin, Erkki J. Brändas, 2006-12-27 Advances in Quantum Chemistry presents surveys of current developments in this rapidly developing field that falls between the historically established areas of mathematics, physics, chemistry, and biology. With invited reviews written by leading international researchers, each presenting new results, it provides a single vehicle for following progress in this interdisciplinary area. Advances in Quantum Chemistry, Volume 51 deals with various aspects of mathematical versus chemical applications. Some parts belong to established scientific domains, where technical progress has been crucial for the development of modern quantum chemistry as well as the quantification problem in spectral resonance analysis. The first chapter in the volume, concerns the calculation of molecular electronic structure to high accuracy, using a variety of one and two-body schemes in the coupled cluster family of methods. Chapter 2 is devoted to Angular Momentum Diagrams. In chapters 3 and 4, the autors portray Chemical Graph Theory (CGT). Advances quantum mechanical signal processing through the fast Padé transform (FPT) are covered in Chapter 5. The concluding chapter gives a mathematical view of molecular equilibria using a Density-Functional Theory (DFT) description. - Publishes articles, invited reviews and proceedings of major international conferences and workshops - Compiled by the leading international researchers in quantum and theoretical chemistry - Highlights the important, interdisciplinary developments |
| double arrow symbol chemistry: The Pearson CSAT Manual 2011 Edgar Thorpe, Showick Thorpe, |
| double arrow symbol chemistry: Arrow Pushing in Organic Chemistry Daniel E. Levy, 2011-09-20 Find an easier way to learn organic chemistry with Arrow-Pushing in Organic Chemistry: An Easy Approach to Understanding Reaction Mechanisms, a book that uses the arrow-pushing strategy to reduce this notoriously challenging topic to the study of interactions between organic acids and bases. Understand the fundamental reaction mechanisms relevant to organic chemistry, beginning with Sn2 reactions and progressing to Sn1 reactions and other reaction types. The problem sets in this book, an excellent supplemental text, emphasize the important aspects of each chapter and will reinforce the key ideas without requiring memorization. |
| double arrow symbol chemistry: Chemistry 2e Paul Flowers, Richard Langely, William R. Robinson, Klaus Hellmut Theopold, 2019-02-14 Chemistry 2e is designed to meet the scope and sequence requirements of the two-semester general chemistry course. The textbook provides an important opportunity for students to learn the core concepts of chemistry and understand how those concepts apply to their lives and the world around them. The book also includes a number of innovative features, including interactive exercises and real-world applications, designed to enhance student learning. The second edition has been revised to incorporate clearer, more current, and more dynamic explanations, while maintaining the same organization as the first edition. Substantial improvements have been made in the figures, illustrations, and example exercises that support the text narrative. Changes made in Chemistry 2e are described in the preface to help instructors transition to the second edition. |
| double arrow symbol chemistry: Chemistry, Kinetics and Thermodynamics Stanford University. Department of Operations Research. Operations Research House, 1970 In the paper the equivalence of three ways of viewing the classical chemical equilibrium problem is discussed. From the point of view of classical chemistry, this problem can be stated as follows: Given the set of reactions that may occur among all the species of a chemical system, their equilibrium constants, and the initial composition of the system (i.e. the amounts of each species present in the system initially), find the equilibrium composition of the system. From the point of view of kinetics, the problem is to determine the evolution of the various parameters describing the system fothe evolution of the various parameters describing the system from their initial values. When the parameters cease to change, the system must be in equilibrium. Given the same system, thermodynamics seeks that composition at which the usable (or free) energy remaining in the system is at a minimum. It can be shown that the system will then be at equilibrium. Much of the materiel contained herein is old. It is presented here in a consistent notation, and in a way intended to emphasize the common aspects of the three points of view. (Author). |
| double arrow symbol chemistry: The Proton: Applications to Organic Chemistry Ross Stewart, 2012-12-02 The Proton: Applications to Organic Chemistry deals with several aspects of the proton drawn from organic chemistry. This book begins with an introductory chapter, followed by discussions on the strengths of neutral organic acids and neutral organic bases. The mode of transfer of hydrogen in its three forms—H+, H•, and H-, alternative sites of protonation or deprotonation of organic compounds, and acid-base chemistry of unstable and metastable species are also elaborated. This text concludes with a presentation of the activation induced in organic molecules by proton addition or removal and its catalytic effects. This publication is intended for practicing organic chemists and researchers conducting work on protons. |
What is the difference between float and double? - Stack Overflow
Dec 31, 2021 · Type double, 64 bits long, has a bigger range (*10^+/-308) and 15 digits precision. Type long double is nominally 80 bits, though a given compiler/OS pairing …
How do I print a double value with full precision using cout?
Dec 17, 2020 · A double is a floating point type, not fixed point. Do not use std::fixed as that fails to print small double as anything but 0.000...000. For large double, it prints …
Difference between long double and double in C and C++
Apr 22, 2015 · The standard only requires that long double is at least as precise as double, so some compilers will simply treat long double as if it is the same as double. But, …
Correct format specifier for double in printf - Stack Overflow
Format %lf is a perfectly correct printf format for double, exactly as you used it. There's nothing wrong with your code. There's nothing wrong with your code. Format %lf …
Reading in double values with scanf in c - Stack Overflow
Oct 7, 2017 · I found out that there is a problem with the length of double on 32 bit OS, so that you are forced to use scanf("%lf", &f) to read in a double. No matter what I …
What is the difference between float and double? - Stack Overflow
Dec 31, 2021 · Type double, 64 bits long, has a bigger range (*10^+/-308) and 15 digits precision. Type long double is nominally 80 bits, though a given compiler/OS pairing may store it as 12 …
How do I print a double value with full precision using cout?
Dec 17, 2020 · A double is a floating point type, not fixed point. Do not use std::fixed as that fails to print small double as anything but 0.000...000. For large double, it prints many digits, …
Difference between long double and double in C and C++
Apr 22, 2015 · The standard only requires that long double is at least as precise as double, so some compilers will simply treat long double as if it is the same as double. But, on most x86 …
Correct format specifier for double in printf - Stack Overflow
Format %lf is a perfectly correct printf format for double, exactly as you used it. There's nothing wrong with your code. There's nothing wrong with your code. Format %lf in printf was not …
Reading in double values with scanf in c - Stack Overflow
Oct 7, 2017 · I found out that there is a problem with the length of double on 32 bit OS, so that you are forced to use scanf("%lf", &f) to read in a double. No matter what I do, second value is …
decimal vs double! - Which one should I use and when?
Jul 22, 2009 · To clear this up double does not have 16 digits - that is only the number of meaningful digits. Floats are based around exponents in base 2 math - some base 10 …
How to Code Double Quotes via HTML Codes - Stack Overflow
Feb 28, 2013 · I was just curious as to why there needs to be 3 different ways to code a double quotes in html codes, for example. – H. Ferrence Commented Feb 28, 2013 at 12:48
Difference between decimal, float and double in .NET?
Mar 6, 2009 · Double: It is also a floating binary point type variable with double precision and 64 bits size(15-17 significant figures). Double are probably the most generally used data type for …
What is the size of float and double in C and C++? [duplicate]
Aug 27, 2014 · The set of values of the type float is a subset of the set of values of the type double; the set of values of the type double is a subset of the set of values of the type long …
What does the !! (double exclamation mark) operator do in …
The double negation operator !! calculates the truth value of a value. It's actually two operators, where !!x means !(!x), and behaves as follows: If x is a false value, !x is true, and !!x is false. If …
