Question

Name the following ions: (a) \(\mathrm{Cu}^{2+}\) (b) \(\mathrm{F}^{-}\) (c) \(\mathrm{Mg}^{2+}\) (d) \(\mathrm{S}^{2-}\)

Short answer

(a) Copper(II); (b) Fluoride; (c) Magnesium; (d) Sulfide.

Step-by-step solution

Identify the Ion Type - Cation or Anion

First, determine if the ion is a cation (positively charged) or an anion (negatively charged). Cations are formed from metals, while anions come from non-metals.

Name the Cation

For cations, use the element's name followed by the charge if needed to distinguish between different possible charges for transition metals. - For \(\mathrm{Cu}^{2+}\), which is a cation, the name is Copper(II). - For \(\mathrm{Mg}^{2+}\), which is also a cation, simply use the element's name: Magnesium.

Name the Anion

For anions, use the root of the element's name with the suffix '-ide.'- For \(\mathrm{F}^{-}\), the ion is named by taking the root 'fluor' and adding '-ide' to get Fluoride.- For \(\mathrm{S}^{2-}\), the root 'sulf' is used with the suffix '-ide,' resulting in Sulfide.

Key concepts

Understanding Cations

Cations are positively charged ions that arise from metal elements. When metals lose one or more of their electrons, they form cations. This happens because metals have a tendency to give away electrons in order to achieve a stable electronic configuration similar to noble gases. - A cation is formed when an atom loses electrons.- Cations possess more protons than electrons.- Metal elements are common sources of cations.For example, the ions - \(\mathrm{Cu}^{2+} \) and - \(\mathrm{Mg}^{2+} \) are both cations derived from copper and magnesium metals, respectively. Naming such ions involves using the element's name, and if the metal can form ions with different charges, the charge is specified in Roman numerals. Therefore, - \(\mathrm{Cu}^{2+}\) is Copper(II). - While - \(\mathrm{Mg}^{2+} \) is simply called Magnesium, as magnesium commonly forms only one type of cation.

Understanding Anions

Anions are negatively charged ions that originate from non-metal elements. Unlike cations, anions are formed when an atom gains electrons, thereby acquiring a stable electron configuration. This is typically the case for elements that lack only a few electrons to attain a full outer shell.- An anion is formed when an atom gains electrons.- Anions have more electrons than protons.- Non-metals are typical candidates for forming anions.The naming of anions involves taking the root of the element's name and adding the suffix '-ide.' For instance:- \(\mathrm{F}^{-}\) becomes Fluoride because we take 'fluor' and add '-ide'.- Similarly, \(\mathrm{S}^{2-}\) becomes Sulfide by attaching '-ide' to 'sulf'.

Transition Metals: Unique Characteristics

Transition metals are an interesting group in the periodic table, known for their ability to form more than one type of cation due to the unique arrangement of their d-electrons. This characteristic often results in transition metal cations with different charges.- Transition metals can form various cations with different charges.- The Roman numeral in the cation's name indicates the charge.- This variability necessitates careful naming.Consider Copper:- \(\mathrm{Cu}^{2+}\) is called Copper(II) to indicate its charge of 2+.These elements are generally found in the central block of the periodic table and are crucial in forming compounds with distinct colors and properties depending on the cation's charge.

Ionic Charge and its Importance

Understanding ionic charge is fundamental in chemistry, as it defines how ions interact and combine to form compounds. Ionic charge results from an imbalance between the number of protons and electrons. - Positive ions have a higher number of protons compared to electrons. - Negative ions possess more electrons than protons. This concept is essential for predicting the formulas of ionic compounds. When naming ions, the charge: - Provides a clue about the number of electrons lost or gained. - Helps in identifying the correct name, especially for those elements that can form multiple ions. In the case of transition metals, the charge information is vital as it prevents confusion and ensures clarity in the compound's chemical identity. A correct understanding of ionic charges ensures accurate communication in chemical naming and formulation.