Question

Some nitrogen atoms have seven neutrons and some have eight neutrons. These two forms of nitrogen are (a) ions of each other; (b) phases of each other; (c) isotopes of each other.

Short answer

The two forms are isotopes of each other.

Step-by-step solution

Understanding the Concept of Isotopes

Isotopes are variants of a chemical element that have the same number of protons but different numbers of neutrons. This means that isotopes differ in their mass number while maintaining the same atomic number.

Examining Nitrogen Atoms Properties

In nitrogen, the atomic number is 7, meaning every nitrogen atom has 7 protons. In this exercise, one form has 7 neutrons, and another form has 8 neutrons. Both shares the same atomic number but differ in their neutron count.

Applying Knowledge to the Options

Comparing the given forms with the options: (a) Ions differ by electron count, not neutrons; thus this is incorrect. (b) Phases refer to states of matter, such as solid, liquid, or gas, also incorrect. (c) Isotopes vary by neutron count, matching our situation with nitrogen.

Conclusion

The two forms of nitrogen, having different numbers of neutrons but the same number of protons, are isotopes of each other according to the definition of isotopes.

Key concepts

Neutrons

Neutrons are subatomic particles found in the nucleus of an atom, right alongside protons. Unlike protons, which have a positive charge, neutrons carry no charge—they are neutral. The primary role of neutrons is to add mass and stability to an atom's nucleus. Atoms of the same element can differ in the number of neutrons they have, which results in different isotopes. These isotopes vary in terms of their mass number. For instance, a nitrogen atom might possess seven neutrons, while another might have eight, leading to different isotopic forms. It's essential to understand that even though the mass changes, the chemical properties usually remain very similar because neutrons do not affect the atom's ability to form chemical bonds. Neutrons are crucial to nuclear reactions and are pivotal in processes like nuclear fission and fusion. Understanding the neutron count is essential in fields such as chemistry and physics, where calculating atomic mass and assessing stability are common tasks.

Atomic Number

An element's atomic number is a fundamental and defining attribute. It indicates the number of protons present in the nucleus of an atom. For each chemical element, the atomic number is unique and constant, which allows elements to be distinguished from one another in the periodic table. For example, nitrogen has an atomic number of 7. This means every nitrogen atom contains 7 protons, no matter which isotope of nitrogen it is. The atomic number is crucial because it determines the element's identity and dictates its place on the periodic table. In chemical reactions and bonds, the atomic number is key as it shows how many electrons an atom must gain, lose, or share to achieve a stable electron configuration. Remember, when comparing isotopes of the same element, though their neutron number might vary, their atomic number—and thus the chemical element—remains unchanged.

Chemical Element

A chemical element is a pure substance consisting entirely of one type of atom, distinguished by its atomic number. Elements are the simplest types of pure substances because they cannot be broken down into simpler substances by normal chemical means. Each element is characterized by a symbol and an atomic number. For example, nitrogen is represented by the symbol 'N' and has an atomic number of 7. There are over 100 known chemical elements, forming the building blocks of matter in the universe. Elements can exist in various forms, including the monoatomic form and more complex molecules, and are categorized based on their properties, such as metals, nonmetals, and metalloids. They are crucial in all kinds of scientific studies, including chemistry and physics, providing the foundation for understanding matter's behavior and interactions.

Nitrogen Isotopes

Nitrogen isotopes are versions of nitrogen that contain the same number of protons but differ in the number of neutrons present in their nuclei. The most common nitrogen isotopes are nitrogen-14 and nitrogen-15. Nitrogen-14 has 7 protons and 7 neutrons, while nitrogen-15 contains 7 protons and 8 neutrons. Despite their differences in neutron count and consequently their mass, these isotopes of nitrogen usually behave almost identically in chemical reactions. Studying nitrogen's isotopes is vital in numerous scientific fields. For instance, nitrogen-15 is often used in agricultural studies to track the movement and usage of nitrogen in the ecosystem, while nitrogen-14's stable nature is important in dating organic materials through radiocarbon dating when it interacts with carbon isotopes.