Textbook Question
Chlorine exists as one of two isotopes with atomic masses of 34.969 amu (35Cl) and 36.966 amu (37Cl) . Calculate the relative abundance of 35Cl and 37Cl based on the average atomic mass of 35.453 amu.
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Ch. 2 - General Chemistry Translated: Finding the Electrons
Mullins1st EditionOrganic Chemistry: A Learner Centered ApproachISBN: 9780137566471
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Table of contents
- Ch. 2 - General Chemistry Translated: Finding the Electrons114
- Ch. 3 - Alkanes and Cycloalkanes: Properties and Conformational Analysis109
- Ch. 4 - Acids and Bases: Electron Flow144
- Ch. 5 - Chemical Reaction Analysis: Thermodynamics and Kinetics118
- Ch. 6 - Stereoisomerism: Arrangement of Atoms in Space112
- Ch. 7 - Principles of Green (Organic) Chemistry3
- Ch. 8 - Alkenes I: Properties and Electrophilic Additions158
- Ch. 9 - Alkenes II: Oxidation and Reduction150
- Ch. 10 - Alkynes: Electrophilic Addition and Redox Reactions101
- Ch. 11 - Properties and Synthesis of Alkyl Halides: Radical Reactions108
- Ch. 12 - Substitution and Elimination: Reactions of Haloalkanes172
- Ch. 13 - Alcohols, Ethers and Related Compounds: Substitution and Elimination239
- Ch. 14 - Structural Identification I: Infrared Spectroscopy and Mass Spectrometry54
- Ch. 15 - Structural Identification II: Nuclear Magnetic Resonance Spectroscopy93
- Ch. 16 - Metals in Organic Chemistry48
- Ch. 17 - Carbonyl Addition Reactions: Aldehydes and Ketones45
- Ch. 18 - Nucleophilic Acyl Substitution I: Carboxylic Acids18
- Ch. 19 - Nucleophilic Acyl Substitution II: Carboxylic Acid Derivatives39
- Ch. 20 - Enolates: Carbonyl Addition and Substitution13
- Ch. 21 - Conjugated Systems I: Stability and Addition Reactions56
- Ch. 22 - Conjugated Systems II: Pericyclic Reactions54
- Ch. 23 - Benzene I: Aromatic Stability and Substitution Reactions64
- Ch. 24 - Benzene II: Reactions Influenced by the Aromatic Ring62
- Ch. 25 - Amines: Structure, Reactions, and Synthesis27
- Ch. 26 - Amino Acids, Proteins, and Peptide Synthesis9
- Ch. 27 - Carbohydrates, Nucleic Acids, and Lipids54
Mullins1st EditionOrganic Chemistry: A Learner Centered ApproachISBN: 9780137566471Not the one you use?Change textbook
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Mullins 1st EditionCh. 2 - General Chemistry Translated: Finding the ElectronsProblem 7
Mullins 1st EditionCh. 2 - General Chemistry Translated: Finding the ElectronsProblem 7Chapter 1, Problem 7
Bromine-79 (50.7% abundance) has an atomic mass of 78.918 amu, whereas bromine-81 (49.3% abundance) has an atomic mass of 80.916 amu. From these data, calculate the average atomic mass of bromine that you would expect to see in the periodic table.
Verified step by step guidance1
Step 1: Understand the concept of average atomic mass. The average atomic mass of an element is calculated as the weighted average of the atomic masses of its isotopes, based on their relative abundances.
Step 2: Write the formula for calculating the average atomic mass:
Step 3: Convert the percentage abundances of bromine-79 and bromine-81 into fractional abundances by dividing each percentage by 100. For bromine-79, the fractional abundance is , and for bromine-81, the fractional abundance is .
Step 4: Substitute the fractional abundances and atomic masses of bromine-79 and bromine-81 into the formula. This gives: .
Step 5: Perform the multiplication and addition to calculate the average atomic mass. This result will represent the average atomic mass of bromine as it appears in the periodic table.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Atomic Mass
Atomic mass is the weighted average mass of an element's isotopes, measured in atomic mass units (amu). It reflects both the mass of each isotope and its relative abundance in nature. For bromine, the atomic masses of its isotopes, bromine-79 and bromine-81, are crucial for calculating the average atomic mass.
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The difference between atomic numbers and atomic mass.
Isotopes
Isotopes are variants of a chemical element that have the same number of protons but different numbers of neutrons, resulting in different atomic masses. In the case of bromine, the two isotopes, bromine-79 and bromine-81, have different atomic masses and relative abundances, which must be considered when calculating the average atomic mass.
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03:06Understanding the hydrogen isotopes.
Weighted Average Calculation
A weighted average calculation involves multiplying each value by its corresponding weight (or abundance) and then summing these products before dividing by the total of the weights. For bromine, this means calculating the contributions of each isotope's mass based on its abundance to find the average atomic mass that appears on the periodic table.
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04:37Draw all of the monochlorination products and calculate percentage yields.
Related Practice
Textbook Question
A chemistry student drew the following incorrect electron configuration for carbon. (a) Correct the diagram.
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Textbook Question
Why is argon considered to be so stable that it is referred to as a noble gas?
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Textbook Question
How many valence shell electrons do each of the following elements contain? How many new bonds can each form?
(c) O
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Textbook Question
A chemistry student drew the following incorrect electron configuration for carbon. (b) Which rule wasn't followed by the student?
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Textbook Question
How many valence shell electrons do each of the following elements contain? How many new bonds can each form?
(b) N
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