
Interpretation:
The reason for change in the mass of an atom when an alpha particle is emittedis to be explained.
Concept introduction:
Elements are found in one or more isotopic forms. Some isotopes have stable nuclei while some have unstable nuclei. Stability of nucleus determines the stability of an isotope. Unstable nucleus will undergo radioactive decay.

Answer to Problem 4E
When an alpha particle is emitted from an atom, mass number of the atom decreases by 4 and
Explanation of Solution
Radioactive isotopes are unstable. To become stable they eject a particle from the nucleus. The process of ejecting particles from the nucleus of an atom is called radioactive decay. Various kinds of subatomic particles are emitted such as alpha particles and beta particles.
When an alpha particle is ejected, the process is called alpha decay. An alpha particle consists of 2 protons and 2 neutrons. It is the same as the nucleus of a helium atom. Hence it can be represented by
When an atom such as uranium undergoes alpha decay, an atom of new element thorium is produced and an alpha particle is produced. New element thorium has 2 protons and 2 neutrons less than uranium. Hence the mass number of uranium decreases by 4 (2 protons and 2 neutrons).
The reaction can be written as:
When an alpha particle is emitted, mass of the atom also changes.
When an alpha particle is emitted from an atom, mass number of the atom decreases by 4 and atomic number decreases by 2. Mass of an atom is concentrated mainly in nucleus. When mass number of an atom changes, its
Chapter U1 Solutions
Living by Chemistry
Additional Science Textbook Solutions
Introductory Chemistry (6th Edition)
Organic Chemistry (8th Edition)
Chemistry: Structure and Properties (2nd Edition)
Chemistry: An Introduction to General, Organic, and Biological Chemistry (13th Edition)
Campbell Biology: Concepts & Connections (9th Edition)
Campbell Essential Biology with Physiology (5th Edition)
- The rate coefficient of the gas-phase reaction 2 NO2 + O3 → N2O5 + O2 is 2.0x104 mol–1 dm3 s–1 at 300 K. Indicate whether the order of the reaction is 0, 1, or 2.arrow_forward8. Draw all the resonance forms for each of the following molecules or ions, and indicate the major contributor in each case, or if they are equivalent. (4.5 pts) (a) PH2 سمةarrow_forward3. Assign absolute configuration (Rors) to each chirality center. a. H Nitz C. он b. 0 H-C. C H 7 C. ་-4 917-417 refs H 1つ ८ ડુ d. Но f. -2- 01 Ho -OH 2HNarrow_forward
- How many signals do you expect in the H NMR spectrum for this molecule? Br Br Write the answer below. Also, in each of the drawing areas below is a copy of the molecule, with Hs shown. In each copy, one of the H atoms is colored red. Highlight in red all other H atoms that would contribute to the same signal as the H already highlighted red. Note for advanced students: In this question, any multiplet is counted as one signal. Number of signals in the 'H NMR spectrum. For the molecule in the top drawing area, highlight in red any other H atoms that will contribute to the same signal as the H atom already highlighted red. If no other H atoms will contribute, check the box at right. No additional Hs to color in top molecule For the molecule in the bottom drawing area, highlight in red any other H atoms that will contribute to the same signal as the H atom already highlighted red. If no other H atoms will contribute, check the box at right. No additional Hs to color in bottom moleculearrow_forwardIn the drawing area below, draw the major products of this organic reaction: 1. NaOH ? 2. CH3Br If there are no major products, because nothing much will happen to the reactant under these reaction conditions, check the box under the drawing area instead. No reaction. Click and drag to start drawing a structure. ☐ : A คarrow_forwardPredict the major products of the following organic reaction: NC Δ ? Some important Notes: • Draw the major product, or products, of the reaction in the drawing area below. • If there aren't any products, because no reaction will take place, check the box below the drawing area instead. • Be sure to draw bonds carefully to show important geometric relationships between substituents. Note: if your answer contains a complicated ring structure, you must use one of the molecular fragment stamps (available in the menu at right) to enter the ring structure. You can add any substituents using the pencil tool in the usual way. Click and drag to start drawing a structure. Х аarrow_forward
- Predict the major products of this organic reaction. Be sure you use dash and wedge bonds to show stereochemistry where it's important. + ☑ OH 1. TsCl, py .... 文 P 2. t-BuO K Click and drag to start drawing a structure.arrow_forwardConsider this organic reaction: ( Draw the major products of the reaction in the drawing area below. If there won't be any major products, because this reaction won't happen at a significant rate, check the box under the drawing area instead. Click and drag to start drawing a structure. Х : а ค 1arrow_forwardIn the drawing area below, draw the major products of this organic reaction: If there are no major products, because nothing much will happen to the reactant under these reaction conditions, check the box under the drawing area instead. 1. NaH 2. CH3Br ? Click and drag to start drawing a structure. No reaction. : ☐ Narrow_forward
- + Predict the major product of the following reaction. : ☐ + ☑ ค OH H₂SO4 Click and drag to start drawing a structure.arrow_forwardConsider this organic reaction: ... OH CI Draw the major products of the reaction in the drawing area below. If there won't be any major products, because this reaction won't happen at a significant rate, check the box under the drawing area instead. ☐ No Reaction. Click and drag to start drawing a structure. : аarrow_forwardConsider the following reactants: Br Would elimination take place at a significant rate between these reactants? Note for advanced students: by significant, we mean that the rate of elimination would be greater than the rate of competing substitution reactions. yes O no If you said elimination would take place, draw the major products in the upper drawing area. If you said elimination would take place, also draw the complete mechanism for one of the major products in the lower drawing area. If there is more than one major product, you may draw the mechanism that leads to any of them. Major Products:arrow_forward
- ChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage LearningChemistryChemistryISBN:9781259911156Author:Raymond Chang Dr., Jason Overby ProfessorPublisher:McGraw-Hill EducationPrinciples of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning
- Organic ChemistryChemistryISBN:9780078021558Author:Janice Gorzynski Smith Dr.Publisher:McGraw-Hill EducationChemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage LearningElementary Principles of Chemical Processes, Bind...ChemistryISBN:9781118431221Author:Richard M. Felder, Ronald W. Rousseau, Lisa G. BullardPublisher:WILEY





