Question

Provide the formula for each of the following monoatomic cations: (a) potassium ion (b) barium ion (c) iron(II) ion (d) tin(II) ion

Short answer

(a) \( K^+ \), (b) \( Ba^{2+} \), (c) \( Fe^{2+} \), (d) \( Sn^{2+} \)

Step-by-step solution

Identify the Element's Symbol

To start, we must identify the chemical symbol for each element. (a) Potassium is represented by the symbol \( K \). (b) Barium is represented by the symbol \( Ba \). (c) Iron is represented by the symbol \( Fe \). (d) Tin is represented by the symbol \( Sn \).

Determine the Charge Based on Ion Name

Next, we examine the charge associated with each monoatomic cation:(a) Potassium ion is \( K^+ \), as potassium forms a \( +1 \) ion.(b) Barium ion is \( Ba^{2+} \), as barium forms a \( +2 \) ion.(c) Iron(II) ion is \( Fe^{2+} \), the (II) indicates a \( +2 \) charge on this iron ion.(d) Tin(II) ion is \( Sn^{2+} \), the (II) indicates a \( +2 \) charge on this tin ion.

Key concepts

Chemical Symbols

Chemical symbols are short abbreviations for chemical elements. They act like unique identifiers for elements in the periodic table. Typically, the first letter of a chemical symbol is uppercase, while the second, if present, is lowercase. For example:

• Potassium is symbolized by \( K \).
• Barium is symbolized by \( Ba \).
• Iron is symbolized by \( Fe \).
• Tin is symbolized by \( Sn \).

These symbols are crucial as they provide a universal shorthand for communicating complex chemical information with clarity and precision. They are used in formulas, equations, and discussions regarding chemistry worldwide.

Ion Charges

Ion charges arise when atoms either lose or gain electrons, resulting in charged particles known as ions. When atoms lose electrons, they become positively charged cations. Conversely, gaining electrons results in negatively charged anions. In monoatomic cations like potassium, barium, iron(II), and tin(II), the number of electrons lost defines the charge.

• Potassium loses one electron, giving it a \( +1 \) charge \( (K^+) \).
• Barium loses two electrons, resulting in a \( +2 \) charge \( (Ba^{2+}) \).
• Iron(II), which is differentiated by the Roman numeral \((II)\), signifies a \( +2 \) charge \( (Fe^{2+}) \).
• Tin(II) also carries a \( +2 \) charge \( (Sn^{2+}) \).

These charges are pivotal as they dictate how ions interact and bond with other atoms or molecules.

Potassium Ion

The potassium ion, symbolized as \( K^+ \), forms when a potassium atom loses one of its outermost electrons. Potassium is an alkali metal located in group 1 of the periodic table, known for typically forming ions with a \( +1 \) charge. The loss of an electron helps potassium achieve a stable electronic configuration, often leading to interactions with anions. These features make potassium ions crucial in various physiological processes such as muscle contraction and nerve function in living organisms.

Barium Ion

Barium ion is represented by \( Ba^{2+} \). This ion forms as a result of barium losing two electrons, resulting in a \( +2 \) charge. Barium belongs to the alkaline earth metals located in group 2 of the periodic table. The \( +2 \) charge is characteristic of this group. Due to its large size and charge, the barium ion often forms ionic compounds that are significant in industries and medical fields, like barium sulfate, a compound used in medical imaging.

Iron(II) Ion

The iron(II) ion, also known as ferrous ion, is denoted as \( Fe^{2+} \). In this state, iron has lost two electrons, resulting in its \( +2 \) charge. This ion is distinguishable by the use of a Roman numeral \((II)\) to denote its oxidation state. Iron can exist in multiple oxidation states, typically forming \( +2 \) and \( +3 \) ions. The iron(II) version is vital as it participates in various biological processes, including oxygen transport in the blood through its role in hemoglobin.

Tin(II) Ion

Tin(II), signified as \( Sn^{2+} \), is a result of tin losing two electrons. The use of \((II)\) in its name indicates its \( +2 \) charge and differentiates it from the higher \( +4 \) oxidation state of tin. This lower oxidation state, like iron, allows tin(II) to form a variety of chemical compounds, often participating in reducing reactions. The existence of these different oxidation factors aids tin’s applications in different chemical and industrial processes, such as in stabilizers and soldering alloys.