Question

Bone Formation The electron capture of strontium-85 can be used by physicians to study bone formation. Write a balanced nuclear equation for this reaction.

Short answer

The balanced nuclear equation for the electron capture of strontium-85 is: \( {}_{38}^{85}Sr + e^- → {}_{37}^{85}Rb + ν \)

Step-by-step solution

Understand the electron capture process

Electron capture is a process in which a proton in an atom's nucleus captures an electron from its orbit around the nucleus and changes into a neutron. This changes the element to a different isotope of another element with a lower atomic number, with the release of a neutrino.

Write the initial nuclear equation

To write the balanced nuclear equation for the electron capture of strontium-85, we first write down the initial nuclear equation, which includes the original isotope, the captured electron, and the unknown final product. \( {}_{38}^{85}Sr + e^- → ? \)

Determine the final product

In electron capture, the number of protons decreases by one because a proton is converted into a neutron. In this case, the atomic number will change from 38 (strontium) to 37 (rhenium). The mass number, however, remains the same as the total number of protons and neutrons is unchanged. So, the final product is an isotope of rhenium: \( {}_{37}^{85}Rb \)

Balance the equation by including the neutrino

It is important to balance the nuclear equation by including the release of a neutrino (ν). Thus, the final balanced nuclear equation for the electron capture of strontium-85 is: \( {}_{38}^{85}Sr + e^- → {}_{37}^{85}Rb + ν \)

Key concepts

Nuclear Equation

A nuclear equation represents a process in the nucleus of an atom, which can involve changes in the atom's identity or structure. In nuclear reactions like electron capture, isotopes may convert to different elements, which is crucially different from chemical reactions that involve only the electrons but not the transformation of elements.

For example, the electron capture of strontium-85 () becomes crucial for our understanding of the process. An electron () from an atom's surroundings is absorbed by a proton in the nucleus, thereby reducing the atomic number by one, but leaving the mass number unchanged because the proton becomes a neutron. This is different from beta decay where a neutron turns into a proton, increasing the atomic number.

The balanced nuclear equation for electron capture contains all initial reactants and resulting products, ensuring conservation of charge and mass number. Here, a neutrino () is released to balance the equation, carrying away energy and maintaining lepton number conservation.

Bone Formation

Bone formation, or ossification, is a vital physiological process taking place in the human body. During bone formation, minerals like calcium and phosphate crystallize on the scaffolding formed by collagen proteins, creating the hard tissue that composes our bones. The ability of bones to incorporate certain isotopes is utilized in medical diagnoses and treatment monitoring.

Isotopes like strontium-85 are chemically similar to calcium, thus they can be absorbed into the bone matrix. Physicians make use of this property by introducing such isotopes into the body, and then tracking their incorporation into bone tissue with imaging techniques. This method allows doctors to study the dynamics of bone formation, assess bone health, and monitor the progress of treatments for conditions like osteoporosis.

Through understanding the principles of electron capture and nuclear equations, we can see how strontium-85's transformation in the body provides critical insights into bone metabolic processes.

Isotopes

Isotopes are variants of a chemical element that have the same number of protons but different numbers of neutrons. Because they have the same number of protons, isotopes share the same position in the periodic table and have similar chemical properties. However, differences in neutron count can lead to variations in their nuclear stability, making some isotopes radioactive.

In medical applications, radioactive isotopes like strontium-85 can be used as tracers because they have the ability to undergo specific nuclear reactions, such as electron capture. The choice of isotope is crucial as it determines the type of radiation it emits and its suitability for a particular diagnosis or treatment. The predictable behavior of isotopes enables physicians to use them effectively, as in the case of strontium-85, which simulates the behavior of calcium and allows the study of bone formation.

Isotopes are fundamental to our understanding of nuclear chemistry and their diverse applications span from medical diagnostics to archaeological dating and environmental monitoring.