Identifying Isotopes Which Two Atoms Are Isotopes Of Each Other

Isotopes are a fundamental concept in chemistry, playing a crucial role in understanding the behavior and properties of elements. Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons. This difference in neutron number leads to variations in atomic mass while maintaining the same atomic number and chemical properties. In this article, we will delve into the concept of isotopes, explore how to identify them, and apply this knowledge to determine which of the given pairs of atoms are isotopes of each other. The question at hand asks us to identify which two atoms from a given set are isotopes. To answer this, we need to understand the defining characteristic of isotopes: they must have the same atomic number (number of protons) but different mass numbers (total number of protons and neutrons). Let's break down the options and apply this concept to find the correct answer. Before diving into the specific options, it's essential to grasp the notation used to represent atoms and their isotopes. An atom is typically represented as ${ }_{Z}^{A}X$, where X is the element symbol, A is the mass number (number of protons + number of neutrons), and Z is the atomic number (number of protons). Isotopes, therefore, will have the same Z value but different A values. Understanding this notation is key to correctly identifying isotopes. Isotopes are atoms of the same element, meaning they have the same number of protons but a different number of neutrons. This difference in neutron number affects the mass number of the atom but does not change its chemical properties. To identify isotopes, we look for atoms with the same atomic number (the subscript) but different mass numbers (the superscript). Isotopes play a crucial role in various scientific applications, including radiometric dating, medical imaging, and nuclear energy. Their unique properties make them invaluable tools in research and technology. By understanding isotopes, we gain a deeper appreciation for the complexity and diversity of the atomic world.

Analyzing the Options

To determine which pair of atoms are isotopes, we need to compare their atomic numbers and mass numbers. Remember, isotopes must have the same atomic number but different mass numbers. We will examine each option individually, applying this principle to identify the correct pair. In this section, we will systematically analyze each option provided to determine which pair of atoms fits the definition of isotopes. We will focus on comparing the atomic numbers and mass numbers of each pair, highlighting the key differences and similarities that help us identify the correct answer. This step-by-step analysis will not only help us solve the problem but also reinforce our understanding of isotopes. The process of identifying isotopes involves careful examination of atomic notation and a clear understanding of the definitions of atomic number and mass number. Let's begin by looking at the first option and proceed through each subsequent option. This methodical approach ensures we don't overlook any crucial details and arrive at the correct conclusion. Understanding the nuances of each option is essential for mastering the concept of isotopes and their identification.

Option A: ${ }_{14}^{27} Si$ and ${ }_{12}^{25} Mg$

In this option, we have silicon (Si) and magnesium (Mg). Silicon has an atomic number of 14 and a mass number of 27, while magnesium has an atomic number of 12 and a mass number of 25. Comparing the atomic numbers, we see that silicon and magnesium have different atomic numbers (14 and 12, respectively). Since isotopes must have the same atomic number, this pair cannot be isotopes. This initial analysis demonstrates the importance of focusing on the atomic number as the primary criterion for identifying isotopes. If the atomic numbers differ, the atoms cannot be isotopes, regardless of any similarities in their mass numbers. This step-by-step evaluation is crucial for a thorough understanding of the concept. The difference in atomic numbers clearly disqualifies this pair from being isotopes, reinforcing the fundamental definition. It's important to remember that isotopes are essentially different forms of the same element, which is why they must share the same atomic number. This option serves as a clear example of atoms that are not isotopes.

Option B: ${ }_{12}^{24} Mg$ and ${ }_{13}^{24} Al$

Here, we have magnesium (Mg) and aluminum (Al). Magnesium has an atomic number of 12 and a mass number of 24, while aluminum has an atomic number of 13 and the same mass number of 24. Again, the atomic numbers are different (12 and 13). Therefore, this pair also cannot be isotopes. The fact that they share the same mass number is irrelevant in determining whether they are isotopes; the crucial factor is the atomic number. This option further emphasizes the importance of atomic number in isotope identification. While the mass numbers being equal might initially seem significant, the differing atomic numbers immediately rule out the possibility of these atoms being isotopes. This highlights a common point of confusion and underscores the necessity of a firm grasp of the definitions. The analysis of this option reinforces the core concept that isotopes are variants of the same element, sharing the same number of protons (atomic number) but differing in the number of neutrons. Understanding this distinction is vital for correctly identifying isotopes.

Option C: ${ }_{12}^{24} Mg$ and ${ }_{12}^{25} Mg$

In this case, we have two forms of magnesium (Mg). One has a mass number of 24, and the other has a mass number of 25. Both have an atomic number of 12. Since the atomic numbers are the same and the mass numbers are different, this pair fits the definition of isotopes. This is the correct answer. The atomic number being the same confirms that these are atoms of the same element, magnesium. The different mass numbers indicate that they have different numbers of neutrons, which is the defining characteristic of isotopes. This option perfectly illustrates the concept of isotopes, demonstrating how the same element can exist in different forms due to variations in neutron count. The presence of the same atomic number and differing mass numbers makes this pair a textbook example of isotopes. This clear-cut case solidifies the understanding of what isotopes are and how to identify them. The analysis of this option provides a positive confirmation of the isotope definition and reinforces the key criteria for their identification.

Option D: ${ }_{11}^{23} Na$ and ${ }_{12}^{25} Mg$

Finally, we have sodium (Na) and magnesium (Mg). Sodium has an atomic number of 11 and a mass number of 23, while magnesium has an atomic number of 12 and a mass number of 25. The atomic numbers are different (11 and 12), so this pair is not isotopes. This option, like options A and B, serves as another example of atoms that are not isotopes. The different atomic numbers immediately disqualify this pair, regardless of any other similarities or differences. This further reinforces the importance of atomic number as the primary determinant of whether two atoms are isotopes. The analysis of this option helps to solidify the understanding of what isotopes are not, which is equally important as knowing what they are. By consistently applying the definition of isotopes, we can confidently identify pairs that do not fit the criteria. This option provides additional practice in distinguishing between isotopes and other atomic relationships.

Conclusion

After analyzing all the options, we can confidently conclude that option C, ${ }_{12}^{24} Mg$ and ${ }_{12}^{25} Mg$, is the correct answer. These two atoms have the same atomic number (12) but different mass numbers (24 and 25), fulfilling the definition of isotopes. Understanding isotopes is crucial in chemistry, as it helps us to comprehend the behavior and properties of elements and their various forms. This exercise has not only identified the correct answer but also reinforced the fundamental principles of isotope identification. The ability to distinguish isotopes from other atomic relationships is a key skill in chemistry. By carefully examining atomic numbers and mass numbers, we can accurately determine whether two atoms are isotopes. This understanding extends beyond this specific question and applies to a wide range of chemical concepts and applications. The concept of isotopes is essential for advanced studies in chemistry and related fields. Mastering this fundamental principle provides a solid foundation for understanding more complex topics. This conclusion not only answers the question but also emphasizes the importance of the underlying chemical principles.