Question

Naturally occurring silver exists as two isotopes having mass numbers 107 and 109. How many protons, neutrons, and electrons are there in each of these isotopes?

Short answer

Silver-107: 47 protons, 60 neutrons, 47 electrons; Silver-109: 47 protons, 62 neutrons, 47 electrons.

Step-by-step solution

Understanding Isotopes

Isotopes are variants of a chemical element that have the same number of protons but different numbers of neutrons. The atomic number defines the number of protons or electrons in an atom.

Identifying Silver's Atomic Number

Silver (Ag) has an atomic number of 47, which means each isotope of silver has 47 protons and 47 electrons because the number of protons equals the number of electrons in a neutral atom.

Calculating Neutrons in Silver-107

The mass number of an isotope is the sum of its protons and neutrons. For Silver-107, with a mass number of 107, the number of neutrons is calculated as follows: \[ \text{Neutrons in } ^{107}\text{Ag} = 107 - 47 = 60 \] Thus, Silver-107 has 60 neutrons.

Calculating Neutrons in Silver-109

Using a similar calculation, for Silver-109 with a mass number of 109, the number of neutrons is: \[ \text{Neutrons in } ^{109}\text{Ag} = 109 - 47 = 62 \] Thus, Silver-109 has 62 neutrons.

Key concepts

Protons: The Defining Feature of an Element

In every atom, protons are the positively charged particles located in the nucleus. They play a crucial role in defining the element's identity. The number of protons, also known as the atomic number, is unique to each element and determines its position on the periodic table. For instance, silver (Ag) has an atomic number of 47, meaning every silver atom contains 47 protons. This number does not change, even if the atom becomes an isotope. Isotopes of an element have identical numbers of protons, ensuring they remain the same element. This consistency of proton count stabilizes the identity of each element, offering a foundational anchor in chemistry.

• Protons provide positive charge to the atom.
• They determine the atomic number and element identity.
• Located in the atomic nucleus alongside neutrons.

Understanding protons helps clarify why elements are distinct and how isotopes still retain their elemental nature despite variations in other parts of the atom.

Neutrons: The Isotope Variation Component

Neutrons are neutrally charged particles found in the nucleus of an atom alongside protons. Their primary function is to add mass and stability to the nucleus. Unlike protons, neutrons do not affect the charge of an atom but significantly contribute to isotopic variation. Isotopes of an element differ by the number of neutrons they possess. For silver, the two isotopes, Silver-107 and Silver-109, have different neutron counts, which are 60 and 62, respectively. Despite this difference in neutrons, both isotopes share the same proton count. The presence of varying numbers of neutrons can influence an isotope's stability and physical properties, without changing its chemical properties.

• Neutrons are neutral particles that add mass to the atom.
• They are vital for the creation of isotopes.
• Nuclear stability is greatly determined by the balance of protons and neutrons.

Mastering the concept of neutrons will enhance your understanding of isotopes and why certain elements have multiple forms.

Electrons: Balancing the Atomic Charge

Electrons are tiny, negatively charged particles that orbit the nucleus of an atom in various energy levels or shells. The number of electrons in a neutral atom equals the number of protons, ensuring that the atom's positive and negative charges are balanced. In the case of silver, each isotope contains 47 electrons, matching its 47 protons. Electrons are responsible for the atom's chemical bonds and reactions, as their arrangements in shells dictate how atoms will interact with one another.

• Electrons have a negative charge and balance out the protons' positive charge.
• Their arrangement determines chemical reactivity and bonding.
• In a neutral atom, the number of electrons equals the number of protons.

Grasping the role of electrons provides insight into how substances combine and form novel compounds, a critical aspect of chemistry.