Question

Metals having \(\mathrm{ns}^{1}\) as the valence electronic configuration: (a) Have a first ionization potential of more than \(10 \mathrm{eV} /\) atom (b) Are highly electropositive (c) Are highly electronegative (d) Act as strong oxidizing reagents

Short answer

Metals with \(\mathrm{ns}^{1}\) configuration are highly electropositive (Option b).

Step-by-step solution

Understand the given electronic configuration

The given electronic configuration is \(\mathrm{ns}^{1}\), which is characteristic of Group 1 elements in the periodic table, such as lithium (Li), sodium (Na), and potassium (K). These elements are known as alkali metals.

Examine the properties of alkali metals

Alkali metals are known for being highly electropositive. This means they have a tendency to lose their valence electron easily to form positive ions (cations). Due to this property, they are not electronegative or strong oxidizing agents. Also, their first ionization potentials are typically less than 10 eV, because the single valence electron is loosely held.

Analyze each option based on electron configuration

- Option (a): Alkali metals generally have ionization potentials of less than 10 eV. Hence, this is not correct. - Option (b): Alkali metals are highly electropositive as they easily lose their outermost electron. This option fits the given configuration. - Option (c): Alkali metals are not electronegative because electronegativity involves gaining electrons, which is contrary to their nature. - Option (d): Alkali metals are not strong oxidizing agents; they typically act as reducing agents.

Key concepts

ns1 electronic configuration

The \(\text{ns}^1\) electronic configuration is a hallmark of Group 1 elements on the periodic table, known as alkali metals. This includes elements like lithium (Li), sodium (Na), and potassium (K). These metals have a single electron in their outermost shell, represented by \(\text{ns}^1\), where "n" is the principal quantum number and varies depending on the period in which the element resides.

• This lone electron is loosely bound due to its distance from the nucleus.
• The \(\text{ns}^1\) configuration makes these elements highly reactive, especially with nonmetals like halogens that need one electron to complete their outer shell.

Understanding the \(\text{ns}^1\) electronic configuration is crucial, as it underlies many of the chemical behaviors and properties of alkali metals, such as their reactivity and tendency to form ionic compounds.

ionization potential of alkali metals

The ionization potential, or ionization energy, is the energy required to remove an electron from a neutral atom in the gaseous state. For alkali metals, this energy is relatively low.

• Since they possess the \(\text{ns}^1\) electronic configuration, the single electron in their outer shell is not tightly held, making it easier to remove.
• The first ionization potential of alkali metals is typically less than 10 eV.
• The lower ionization potential reflects the high tendency of these metals to lose electrons and form positive ions or cations.

This property is a driving force behind their high reactivity, as alkali metals readily participate in chemical reactions by donating their outer electron.

electropositivity of alkali metals

Electropositivity refers to the tendency of an element to lose electrons and form positive ions, and alkali metals are among the most electropositive elements.

• This trait emanates from their \(\text{ns}^1\) configuration, as the single electron can be easily lost, leading to the formation of stable cations.
• Electropositivity increases down the group, meaning heavier alkali metals like cesium and francium are more electropositive than lithium.

Being highly electropositive, alkali metals vigorously react with nonmetals, especially halogens, to form ionic bonds, making them crucial in various chemical applications and reactions.

oxidizing vs reducing agents

In chemistry, oxidizing and reducing agents are substances that, respectively, accept and donate electrons during chemical reactions. Alkali metals are specifically strong reducing agents.

• A reducing agent donates electrons to another substance, causing it to be reduced, while the agent itself gets oxidized.
• Alkali metals, with their \(\text{ns}^1\) configuration, readily lose their valence electron, making them excellent reducing agents.
• They often donate electrons to substances, thus enabling the formation of ionic compounds.

Conversely, oxidizing agents gain electrons and are not a typical role for alkali metals, which prefer oxidation over reduction. This reactivity underscores their importance in redox reactions, commonly seen in various industrial and chemical processes.