Polonium-210 Decay What Stable Atom Is Formed

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Polonium-210, a radioactive isotope of polonium, undergoes alpha decay, a fascinating nuclear transformation process. This process involves the emission of an alpha particle, which is essentially a helium nucleus, consisting of two protons and two neutrons. The central question we aim to address is: What stable atom results from the decay of Polonium-210? Understanding radioactive decay is crucial in various fields, including nuclear chemistry, environmental science, and medicine. In this comprehensive guide, we will delve deep into the intricacies of Polonium-210 decay, exploring the underlying principles and arriving at the correct answer. We will also explore the broader context of alpha decay and its significance in the realm of nuclear transformations.

Understanding Alpha Decay: The Fundamentals

To accurately determine the stable atom produced after Polonium-210 decay, it's essential to grasp the concept of alpha decay. Alpha decay is a type of radioactive decay where an atomic nucleus emits an alpha particle. This alpha particle, as mentioned earlier, is equivalent to a helium nucleus ($ {}_2^4 He $), comprising two protons and two neutrons. When an atom undergoes alpha decay, its atomic number (the number of protons) decreases by 2, and its mass number (the total number of protons and neutrons) decreases by 4. This transformation results in the formation of a new element, often referred to as the daughter nucleus. This fundamental principle governs the transmutation of elements through radioactive decay.

The generic equation representing alpha decay can be written as:

$ {}_Z^A X ightarrow {}2^4 He + {}{Z-2}^{A-4} Y $

Where:

  • $ {}_Z^A X $ represents the parent nucleus, the original radioactive atom.
  • $ {}_2^4 He $ represents the alpha particle.
  • $ {}_{Z-2}^{A-4} Y $ represents the daughter nucleus, the atom formed after the decay.
  • Z represents the atomic number (number of protons).
  • A represents the mass number (number of protons and neutrons).

Key takeaway: Alpha decay involves the ejection of a helium nucleus from the parent nucleus, leading to a decrease in both atomic number and mass number.

Deciphering Polonium-210 Decay: A Step-by-Step Analysis

Now, let's apply this understanding to the specific case of Polonium-210 ($ {}_{84}^{210} Po $) decay. The decay equation provided is:

$ {}_{84}^{210} Po ightarrow ext{? } + {}_2^4 He $

Our objective is to identify the daughter nucleus, represented by the question mark. To do this, we need to apply the principles of conservation of mass number and atomic number.

  1. Conservation of Mass Number: The mass number on the left side of the equation (Polonium-210) is 210. The mass number of the alpha particle is 4. Therefore, the mass number of the daughter nucleus must be 210 - 4 = 206.
  2. Conservation of Atomic Number: The atomic number on the left side of the equation (Polonium-210) is 84. The atomic number of the alpha particle is 2. Therefore, the atomic number of the daughter nucleus must be 84 - 2 = 82.

Thus, the daughter nucleus has a mass number of 206 and an atomic number of 82. By consulting the periodic table, we can identify the element with an atomic number of 82 as lead (Pb). Therefore, the daughter nucleus is Lead-206 ($ {}_{82}^{206} Pb $).

The complete decay equation for Polonium-210 is:

$ {}{84}^{210} Po ightarrow {}{82}^{206} Pb + {}_2^4 He $

Key takeaway: By applying the conservation laws of mass number and atomic number, we can accurately identify the daughter nucleus formed during alpha decay.

The Correct Answer: Lead-206 ($ {}_{82}^{206} Pb $)

Based on our analysis, the stable atom that results from the decay of Polonium-210 is Lead-206 ($ {}_{82}^{206} Pb $). This corresponds to option A in the given choices.

Option B, $ {}_{84}^{210} Po ^{-} $, represents a polonium ion with an extra electron. While ions can form, this is not the direct result of alpha decay. Alpha decay involves nuclear changes, not the gain or loss of electrons. Therefore, this option is incorrect.

Key takeaway: Lead-206 is the stable daughter nucleus produced after Polonium-210 undergoes alpha decay.

The Significance of Alpha Decay and Polonium-210

Alpha decay, as exemplified by the decay of Polonium-210, is a fundamental process in nuclear physics and chemistry. Understanding alpha decay is crucial for comprehending the behavior of radioactive materials and their applications. Alpha decay plays a significant role in:

  • Nuclear Reactions: Alpha decay is a type of nuclear reaction, where the nucleus of an atom changes its composition.
  • Radioactive Dating: Alpha decay is utilized in radioactive dating techniques to determine the age of geological samples and artifacts.
  • Nuclear Medicine: Alpha-emitting isotopes are used in targeted cancer therapies, where the alpha particles can destroy cancer cells with minimal damage to surrounding healthy tissues.
  • Industrial Applications: Alpha emitters are used in various industrial applications, such as smoke detectors, where the alpha particles ionize air and create a current. Smoke particles disrupt this current, triggering the alarm.

Polonium-210, in particular, has a relatively short half-life of 138 days. This means that half of a sample of Polonium-210 will decay into Lead-206 in 138 days. This property makes it useful in certain applications, but also necessitates careful handling due to its radioactivity.

Key takeaway: Alpha decay has diverse applications across various scientific and industrial fields, highlighting its importance in our understanding of the world around us.

Exploring Further: Radioactive Decay Series

The decay of Polonium-210 is often part of a larger sequence of radioactive decays known as a decay series. A radioactive decay series is a sequence of decays that radioactive elements go through until a stable isotope is achieved. Polonium-210 is part of the uranium decay series, which starts with Uranium-238 and eventually leads to stable Lead-206. Understanding decay series is crucial for:

  • Predicting Radioactive Byproducts: Decay series help us predict the various radioactive isotopes that will be produced as a result of the decay of a parent nucleus.
  • Radioactive Waste Management: Knowledge of decay series is essential for managing radioactive waste, as it allows us to anticipate the long-term radioactive behavior of the waste materials.
  • Environmental Monitoring: Decay series information is vital for monitoring the presence and movement of radioactive materials in the environment.

Key takeaway: Radioactive decay series provide a comprehensive view of the transformations radioactive elements undergo, leading to stable isotopes.

Conclusion: Mastering Alpha Decay and Polonium-210

In conclusion, we have successfully identified the stable atom resulting from the decay of Polonium-210. Through a detailed analysis of alpha decay principles and the conservation laws of mass number and atomic number, we determined that Lead-206 ($ {}_{82}^{206} Pb $) is the stable daughter nucleus. This understanding is fundamental to comprehending nuclear transformations and the behavior of radioactive materials.

Furthermore, we explored the significance of alpha decay in various fields, including nuclear medicine, radioactive dating, and industrial applications. We also touched upon the concept of radioactive decay series, highlighting their importance in predicting radioactive byproducts and managing radioactive waste.

By grasping the intricacies of Polonium-210 decay and alpha decay in general, we gain a deeper appreciation for the fascinating world of nuclear chemistry and the diverse applications of radioactive isotopes. This knowledge empowers us to address challenges and harness the potential of nuclear processes for the benefit of society.