Radioactive cobalt-60 is used to study defects in vitamin \(\mathrm{B}_{12}\) absorption because cobalt is the metallic atom at the center of the vitamin \(\mathrm{B}_{12}\) molecule. The nuclear synthesis of this cobalt isotope involves a three-step process. The overall reaction is iron-58 reacting with two neutrons to produce cobalt-60 along with the emission of another particle. What particle is emitted in this nuclear synthesis? What is the binding energy in J per nucleon for the cobalt-60 nucleus (atomic masses: \(^{60} \mathrm{Co}=\) $59.9338 \mathrm{u} ;^{-1} \mathrm{H}=1.00782$ u)? What is the de Broglie wavelength of the emitted particle if it has a velocity equal to \(0.90 c,\) where \(c\) is the speed of light?

Short Answer

Expert verified
The particle emitted during the nuclear synthesis of cobalt-60 is a beta particle (\(\beta^{-}\)). The binding energy per nucleon for the cobalt-60 nucleus is approximately \(\frac{1.60287 \times 10^{-13}}{60}\ \mathrm{J} / \mathrm{nucleon}\). The de Broglie wavelength of the emitted particle with a velocity equal to \(0.90 c\) is approximately \(2.7 \times 10^{-15}\ \mathrm{m}\).

Step by step solution

01

Nuclear synthesis of cobalt-60

First, we need to examine the following reaction for the nuclear synthesis involving iron-58 and two neutrons: \[^{58} \mathrm{Fe} + 2^{1} \mathrm{n} \rightarrow ^{60} \mathrm{Co} + X\] where X is the unknown emitted particle. Let's find the missing particle by calculating the mass number and atomic number of the missing particle, X: Mass number of X = Mass number of reactants - Mass number of products Atomic number of X = Atomic number of reactants - Atomic number of products Reactants atomic number: \(Z_{Fe} = 26\), \(Z_n = 0\) Reactants mass number: \(A_{Fe} = 58\), \(A_n = 1\) Product atomic number: \(Z_{Co} = 27\) Product mass number: \(A_{Co} = 60\) Now, let's substitute the values in the equations and find the values for X: Mass number of X = (58 + 2 - 60) = 0 Atomic number of X = (26 + 0 - 27) = -1 The emitted particle, X, has a mass number of 0 and an atomic number of -1, which corresponds to an electron or a beta particle, (\(\beta^{-}\)). Hence, the nuclear synthesis equation is: \[^{58} \mathrm{Fe} + 2^{1} \mathrm{n} \rightarrow ^{60} \mathrm{Co} + \beta^{-}\]
02

Binding energy per nucleon

As we know the atomic masses of cobalt-60 and hydrogen atom, we can calculate the binding energy per nucleon using the formula: Binding energy = \((Zm_H + Nm_n - m)(c^2)\) where \(Z\) is the atomic number of cobalt-60, \(N\) is the number of neutrons, \(m_H\) is the mass of 1 hydrogen atom, \(m_n\) is the mass of 1 neutron, and \(m\) is the given atomic mass of cobalt-60. Now, let's substitute the values: \(Z = 27\) \(N = 33\) \(m_H = 1.00782\ \mathrm{u}\) \(m_n = 1.00867\ \mathrm{u}\) \(m = 59.9338\ \mathrm{u}\) Binding energy = \(((27)(1.00782) + (33)(1.00867) - 59.9338)(c^2)\) Converting atomic mass units (u) to kilograms (kg): Binding energy = \(((27)(1.00782 \times 1.66 \times 10^{-27}) + (33)(1.00867 \times 1.66 \times 10^{-27} ) - (59.9338 \times 1.66 \times 10^{-27}))(9 \times 10^{16})\). Binding energy = \(1.60287 \times 10^{-13}\ \mathrm{J}\). To find the binding energy per nucleon, we divide the total binding energy by the number of nucleons: Binding energy per nucleon = \(\frac{1.60287 \times 10^{-13}}{60}\ \mathrm{J} / \mathrm{nucleon}\).
03

de Broglie wavelength of the emitted particle

The de Broglie wavelength is given by: \(\lambda = \frac{h}{mv}\), where \(h\) is the Planck's constant, \(m\) is the mass of the particle, and \(v\) is the velocity of the particle. We know the emitted particle is a beta particle (electron), and its mass (\(m_e\)) is approximately \(9.11 \times 10^{-31}\ \mathrm{kg}\), and the velocity is \(0.90c\). The speed of light \(c = 3 \times 10^8\ \mathrm{m/s}\). So, the velocity of electron is \(v_e = (0.90) (3 \times 10^8) = 2.7 \times 10^8\ \mathrm{m/s}\). Planck's constant (\(h\)) is \(6.626 \times 10^{-34}\ \mathrm{J\cdot s}\). Now, let's substitute the values: \(\lambda = \frac{6.626 \times 10^{-34}}{(9.11 \times 10^{-31})(2.7 \times 10^8)}\). After calculating, we find the de Broglie wavelength of the emitted particle: \(\lambda = 2.7 \times 10^{-15}\ \mathrm{m}\).

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A small atomic bomb releases energy equivalent to the deto- nation of \(20,000\) tons of TNT; a ton of TNT releases \(4 \times 10^{9} \mathrm{J}\) of energy when exploded. Using \(2 \times 10^{13} \mathrm{J} / \mathrm{mol}\) as the energy released by fission of \(^{235} \mathrm{U}\) , approximately what mass of \(^{235} \mathrm{U}\) undergoes fission in this atomic bomb?

Write an equation describing the radioactive decay of each of the following nuclides. (The particle produced is shown in parentheses, except for electron capture, where an electron is a reactant.) a. 68 Ga (electron capture) b. 62 Cu (positron) c. 212 \(\mathrm{Fr}(\alpha)\) d. 129 \(\mathrm{Sb}(\beta)\)

Why are the observed energy changes for nuclear processes so much larger than the energy changes for chemical and physical processes?

When using a Geiger-Müller counter to measure radioactivity, it is necessary to maintain the same geometrical orientation between the sample and the Geiger-Muller tube to compare different measurements. Why?

A chemist studied the reaction mechanism for the reaction $$ 2 \mathrm{NO}(g)+\mathrm{O}_{2}(g) \longrightarrow 2 \mathrm{NO}_{2}(g) $$ by reacting \(\mathrm{N}^{16} \mathrm{O}\) with \(^{18} \mathrm{O}_{2}\) . If the reaction mechanism is $$ \begin{aligned} \mathrm{NO}+\mathrm{O}_{2} & \rightleftharpoons \mathrm{NO}_{3}(\text { fast equilibrium }) \\ \mathrm{NO}_{3}+\mathrm{NO} & \longrightarrow 2 \mathrm{NO}_{2}(\text { slow }) \end{aligned} $$ what distribution of \(^{18} \mathrm{O}\) would you expect in the NO \(_{2} ?\) Assume that \(\mathrm{N}\) is the central atom in \(\mathrm{NO}_{3},\) assume only \(\mathrm{N}^{16} \mathrm{O}^{16} \mathrm{O}_{2}\) forms, and assume stoichiometric amounts of reactants are combined.

See all solutions

Recommended explanations on Chemistry Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free