Question

Give the charge each atom takes when it forms an ion. If more than one charge is possible, list both. a) \(\mathrm{K}\) b) \(\mathrm{O}\) c) \(\mathrm{Co}\) a) \(\mathrm{K}\) b) O c) Co

Short answer

K: \(+1\), O: \(-2\), Co: \(+2\) or \(+3\).

Step-by-step solution

Understand the Exercise

The task is to determine the possible ion charges for each given element: Potassium (K), Oxygen (O), and Cobalt (Co). Ionic charges typically reflect the electrons lost or gained by these elements to achieve a stable electron configuration.

Determine the Charge for Potassium (K)

Potassium (K) is an alkali metal found in Group 1 of the periodic table. Atoms in this group typically lose one electron to achieve a noble gas electron configuration. Therefore, potassium forms a cation with a charge of \( +1 \).

Determine the Charge for Oxygen (O)

Oxygen (O) is a non-metal found in Group 16 of the periodic table. Atoms in this group typically gain two electrons to complete their valence shell. Thus, oxygen forms an anion with a charge of \( -2 \).

Determine the Charge(s) for Cobalt (Co)

Cobalt (Co) is a transition metal, which frequently exhibits more than one common oxidation state. The most common ion charges for cobalt are \( +2 \) and \( +3 \). Therefore, cobalt can form cations with charges of \( +2 \) or \( +3 \).

Key concepts

Potassium Ions

Potassium, represented by the symbol \( \mathrm{K} \), is part of the alkali metals family in Group 1 of the periodic table. Like its fellow alkali metals, potassium tends to lose electrons rather readily to achieve a stable electron configuration similar to noble gases. Importantly, potassium atoms have a single electron in their outer shell, which they lose to form ions.

When potassium forms an ion, it results in the loss of one electron. This process leaves behind more protons than electrons in the atom, creating a positive charge. Thus, potassium forms a cation with a +1 charge, represented as \( \mathrm{K^+} \).

• **Group 1 Family Trait:** Alkali metals like potassium lose one electron easily.
• **Electron Configuration Objective:** Achieving stability like noble gases.
• **Resulting Ion:** \( \mathrm{K^+} \) cation with a charge of +1.

Understanding this behavior is crucial in chemistry when predicting how potassium behaves in reactions, particularly in formulating compounds where it often bonds with nonmetals to form ionic compounds.

Oxygen Ions

Oxygen, denoted by the symbol \( \mathrm{O} \), is a non-metal that belongs to Group 16, often referred to as the chalcogens in the periodic table. Elements in this group are known to gain electrons to fill their valence shells, which aids in achieving a stable electron arrangement akin to the nearest noble gas configuration.

For oxygen, the valence shell needs two more electrons to be filled. During ion formation, oxygen typically gains two electrons. As it acquires these extra electrons, the number of electrons surpasses the number of protons, resulting in a negatively charged ion. Consequently, oxygen forms an anion with a charge of -2, expressed as \( \mathrm{O^{2-}} \).

• **Group 16 Family Trait:** Tendency to gain two electrons.
• **Filled Valence Objective:** Stability similar to noble gases.
• **Resulting Ion:** \( \mathrm{O^{2-}} \) anion with a charge of -2.

This trait is instrumental in numerous chemical processes, such as oxide formation, where oxygen combines with metals to form stable ionic compounds.

Cobalt Ions

Cobalt, symbolized as \( \mathrm{Co} \), is a member of the transition metals group. Transition metals are characterized by their ability to form ions with different charges, owing to their variable oxidation states. This property makes them quite unique and versatile in various chemical reactions.

Cobalt can commonly exist in oxidation states of +2 and +3. In the +2 state, cobalt loses two electrons, which is typical for transition metals; this is seen as \( \mathrm{Co^{2+}} \). When cobalt loses three electrons, it forms the +3 oxidation state, represented as \( \mathrm{Co^{3+}} \).

• **Versatile Oxidation States:** Cobalt can form \( \mathrm{Co^{2+}} \) and \( \mathrm{Co^{3+}} \) ions.
• **Transitional Metal Quality:** Ability to adopt various charges.
• **Common Charge States:** +2 and +3, significant in alloy formation and catalytic processes.

Cobalt's ability to operate in different ionic states is crucial for its role in forming complex metallic structures and its vital function in industrial applications, including its catalytic properties in chemical industries.