Question

Mercurous ion is represented as (a) \(\mathrm{Hg}^{2+}\) (b) \(\mathrm{Hg}_{2}^{+}\) (c) \(\mathrm{Hg}_{2}^{2+}\) (d) \(\mathrm{Hg}^{-}+\mathrm{Hg}^{2+}\)

Short answer

Mercurous ion is represented as (c) \( \mathrm{Hg}_2^{2+} \).

Step-by-step solution

Understanding the Mercurous Ion

The mercurous ion arises from mercury, which can form different types of ions. Mercurous ions are specifically formed when two mercury atoms share a divalent charge, creating a dimer. This ion is typically written as Hg in a dimeric form with a total charge of "+2".

Identifying the Correct Formula

Given choices are Hg²⁺, Hg₂⁺, Hg₂²⁺, and Hg⁻ + Hg²⁺. Among these, the mercurous ion, which is the dimer with a +2 charge overall, is represented as Hg₂²⁺. This reflects the two Hg atoms sharing the charge across the dimer.

Answer Explanation

The mercurous ion, Hg₂²⁺, consists of two mercury atoms, each contributing to a shared positive two charge. This contrasts with the monomeric forms mentioned in other choices.

Key concepts

Chemical Nomenclature

Chemical nomenclature is like the language of chemistry. It's how scientists talk about substances and their properties without confusion. Understanding this system helps us communicate exactly what compounds or elements we're dealing with.
In terms of ions, nomenclature tells us a lot about the ion's charge and how elements combine. For ions like the mercurous ion, the name reflects not just the element (mercury) but also its ionic form.
In chemical recipes, ion names give clues about the structure and the charge balance each part maintains. The mercurous ion, for instance, is defined by chemists as "Hg" with a dimeric form and a "+2" charge. Without the systematic naming, it would be challenging to discern such critical differences in chemical behavior.

Divalent Cations

Divalent cations are ions with a positive charge of +2. They play crucial roles in chemistry due to their stable electron arrangements.
Mercury can form divalent cations, but it has a unique twist. Instead of simply being a single atom with a +2 charge, it can pair with another mercury atom, forming a dimeric cation.
In the case of the mercurous ion, the charge is shared between two mercury atoms, which creates a connection, or bonding, between them. This shared charge results in the formula \( \text{Hg}_2^{2+} \).
Divalent cations like these are not just about balancing charges. They also involve understanding the configuration that enables such bonding. That's why proper nomenclature and notation are vital to expressing what happens on the atomic level.

Dimeric Ions

Dimeric ions are quite interesting, as they're not just a single atom carrying a charge. Instead, they're combinations of two or more atoms. These atoms typically hold the charge together, which affects their chemical properties.
The mercurous ion is the perfect example of a dimeric ion. Rather than being a single Hg atom, it consists of two Hg atoms bonded together, collectively carrying a \( +2 \) charge.
Understanding dimeric ions isn't just about knowing their chemical equation, but also about visualizing how these atoms bind and stabilize each other through shared charges. This stabilization is crucial, especially in reactions where precise charge balancing is needed for result prediction.
Dimeric ions such as \( \text{Hg}_2^{2+} \) also showcase how elements like mercury can exhibit multiple forms in chemical reactions, further highlighting the importance of accurate chemical notation.

Mercury Compounds

Mercury compounds are fascinating due to mercury's ability to form different kinds of ions and compounds. Understanding these helps us grasp the diverse chemistry of mercury.
Mercury can appear as mercurous \( (\text{Hg}_2^{2+}) \) or mercuric \( (\text{Hg}^{2+}) \), showing its versatile nature. The mercurous ion involves a pair of atoms sharing a \( +2 \) charge, while the mercuric ion is a single atom with a \( +2 \) charge.
Mercury compounds are known for their applications in various fields, including medicine and industry. However, they must be handled with care due to mercury's toxicity.
Understanding these compounds is not only important for practical applications but also for recognizing the environmental impacts they may have. The right use of such chemical knowledge helps in designing safer and more effective technologies.