Textbook Question
Write isotopic symbols in the form X-A (e.g., C-13) for each isotope. b. the gold isotope with 119 neutrons
Ch.2 - Atoms & Elements
Tro6th EditionChemistry: A Molecular ApproachISBN: 9780137832217
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Table of contents
- Ch.1 - Matter, Measurement & Problem Solving118
- Ch.2 - Atoms & Elements106
- Ch.3 - Molecules and Compounds131
- Ch.4 - Chemical Reactions and Chemical Quantities56
- Ch.5 - Introduction to Solutions and Aqueous Solutions82
- Ch.6 - Gases114
- Ch.7 - Thermochemistry96
- Ch.8 - The Quantum-Mechanical Model of the Atom60
- Ch.9 - Periodic Properties of the Elements90
- Ch.10 - Chemical Bonding I: The Lewis Model89
- Ch.11 - Chemical Bonding II: Molecular Shapes, VSEPR & MO Theory85
- Ch.12 - Liquids, Solids & Intermolecular Forces51
- Ch.13 - Solids & Modern Materials47
- Ch.14 - Solutions90
- Ch.15 - Chemical Kinetics115
- Ch.16 - Chemical Equilibrium68
- Ch.17 - Acids and Bases136
- Ch.18 - Aqueous Ionic Equilibrium153
- Ch.19 - Free Energy & Thermodynamics93
- Ch.20 - Electrochemistry106
- Ch.21 - Radioactivity & Nuclear Chemistry74
- Ch.22 - Organic Chemistry140
Chapter 2, Problem 52
A helium nucleus has two protons and two neutrons. How many electrons does it take to equal the mass of a helium nucleus?
Verified step by step guidance1
Step 1: Understand that the mass of a helium nucleus is made up of the mass of two protons and two neutrons. The mass of a proton is approximately 1.67 x 10^-27 kg and the mass of a neutron is approximately 1.67 x 10^-27 kg. Therefore, the total mass of a helium nucleus is approximately 4 x 1.67 x 10^-27 kg.
Step 2: Know that the mass of an electron is approximately 9.11 x 10^-31 kg.
Step 3: To find out how many electrons it would take to equal the mass of a helium nucleus, you would divide the mass of the helium nucleus by the mass of an electron.
Step 4: Set up the equation: (4 x 1.67 x 10^-27 kg) / (9.11 x 10^-31 kg) = number of electrons.
Step 5: Solve the equation to find the number of electrons. Remember, the number of electrons should be a whole number as you cannot have a fraction of an electron.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Atomic Structure
An atom consists of a nucleus containing protons and neutrons, surrounded by electrons in orbitals. The number of protons defines the element, while neutrons contribute to the atomic mass. In helium, the nucleus has two protons and two neutrons, making it a stable and light element.
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Mass of Subatomic Particles
The mass of subatomic particles varies, with protons and neutrons having a mass of approximately 1 atomic mass unit (amu) each, while electrons are significantly lighter, about 1/1836 of a proton's mass. This difference is crucial when comparing the mass of electrons to that of a nucleus.
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Mass-Electron Equivalence
To determine how many electrons would equal the mass of a helium nucleus, one must compare the total mass of the nucleus (approximately 4 amu) to the mass of an electron. Since one electron has a mass of about 0.00055 amu, it would take a large number of electrons to match the mass of the helium nucleus.
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Related Practice
Textbook Question
Write isotopic symbols in the form X-A (e.g., C-13) for each isotope. c. the gold isotope with 122 neutrons
Textbook Question
Write isotopic symbols in the form X-A (e.g., C-13) for each isotope. a. the hydrogen isotope with two neutrons
Textbook Question
Which statements about subatomic particles are true? a. If an atom has an equal number of protons and electrons, it will be charge-neutral. b. Electrons are attracted to protons. c. Electrons are much lighter than neutrons. d. Protons have twice the mass of neutrons.
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Textbook Question
How many electrons does it take to equal the mass of a proton?
Textbook Question
Which statements about subatomic particles are false? a. Protons and electrons have charges of the same magnitude but opposite sign. b. Protons have about the same mass as neutrons. c. Some atoms don't have any protons. d. Protons and neutrons have charges of the same magnitude but opposite signs.
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