Electropositive Elements: Definitions, Examples, Radicals, Electronegativity, List of Top 5, Periodic Trends, and Sample Questions

Electropositive Elements Overview

In chemistry, the periodic table is an important tool for categorizing elements based on their atomic structure, characteristics, and behavior. Elements are classed based on their electronegativity, with some being electropositive. Electropositive elements are those that shed electrons readily, resulting in the creation of positively charged ions (cations). The propensity of an atom to give off electrons and create positively charged cations is known as electropositivity. To create chemical compounds, chemical processes either lose or acquire electrons. When charged electrons are attracted to or repellent towards chemical elements, the terms "electronegativity" and "electropositivity" are used to describe this. The capacity of a chemical element to gain electrons to create negatively charged electrons is known as electronegativity, whereas the ability of a chemical element to lose electrons to produce a positively charged cation is known as electropositivity. The reverse of electronegativity is electropositivity.

What are Elements?

A fundamental object that is difficult to divide into smaller bits is known as an element. An element is a material that cannot be broken down by non-nuclear processes in chemistry and physics. A discrete component of a larger system or collection is referred to as an "element" in computers and mathematics.

What is Electropositivity?

Electropositivity is a measurement of an element's capacity to provide electrons for the creation of positive ions, primarily a metal. Electronegative elements, on the other hand, are those that may readily take electrons for the creation of negative ions. Electronegative elements include things like non-metals. As a result, materials that release light have extremely low electronegativities, and extremely high-energy electrons have extremely low electropositivities. Electropositive metals often do not accept electrons to create anions, whereas electronegative elements typically have no metals and a tendency to lose electrons to form cations. Normally, the most electropositive and electronegative elements combine to produce ionic salts. 

Read more about the Reactivity Series of Metals.

What are Electropositive Elements?

The elements are often split into two categories in a periodic table, which are as follows-

1. Metals
2. Non-Metals

Additionally, the non-metals and metals are separated into electropositive and electronegative groups. Metals and hydrogen that are acidic are two examples of electropositive elements or groups. The definition of an electropositive element is one whose electrode potential is higher than the electrode potential of a conventional hydrogen electrode, which is given an arbitrary value of zero. The univalent alkali metals Li+, Na+, K+, etc. are a few examples. Be²+, Mg²+, and Ca²+ are a few examples of divalent alkaline earth metals. 

Properties of Electropositive Elements: 

Electropositive elements have unique features that set them apart from other elements in the periodic table. Some important characteristics of electropositive elements include: 

• Metallic sheen: Electropositive materials frequently have a metallic sheen, indicating their capacity to conduct electricity and heat due to the presence of free electrons in their atomic structure. 
• High Melting and Boiling Points; Electropositive elements have high melting and boiling temperatures, indicating strong metallic bonding between atoms in their solid form. 
• Ductility & Malleability: Electropositive elements are ductile and malleable, which means they may be pulled into wires or hammered into thin sheets without breaking, due to electron mobility in their atomic structure.
• Good Conductivity: Electropositive elements are efficient conductors of electricity and heat because they include delocalized electrons that may easily travel inside the metallic lattice. 
• Reactivity: Electropositive elements are very reactive, particularly with nonmetals, since they lose electrons and create positive ions in chemical processes. 
• Tendency to Form Cations: Electropositive materials may easily create positively charged ions (cations) by losing electrons to obtain a stable electron configuration.

Examples of Electropositive Elements

The periodic table contains several electropositive elements across different groups and periods. Some prominent examples of electropositive elements include:

• Alkali Metals (Group 1): Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs), and Francium (Fr).
• Alkaline Earth Metals (Group 2): Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba), and Radium (Ra).
• Transition Metals: Some transition metals also exhibit electropositive behavior, particularly in their lower oxidation states. Examples include Iron (Fe), Copper (Cu), Zinc (Zn), and Nickel (Ni).
• Rare Earth Metals: The lanthanides and actinides also exhibit electropositive behavior, particularly in their lower oxidation states. Examples include Lanthanum (La), Cerium (Ce), Uranium (U), and Thorium (Th).

What are Electropositive Radicals?

Atoms, ions, or molecules that have the ability to lose an electron and have a positive electrical charge are known as electropositive radicals. Due to a chemical species' tendency to lose electrons and produce positive radicals, the electropositive characteristic of that chemical species causes an electropositive radical to arise. Additionally, some examples of electropositive radicals include the cations sodium (Na+), calcium (Ca+²), and others.

What is Electronegativity?

The ability of a metal in an atom or molecule to draw electrons on its own is referred to as "electronegativity." It is only a habit, so it is the perfect material. It demonstrates the full impact of the atomic propensity on various things by drawing the pairs that make up electrons. Calculate the electronegativity on various scales. Linus Pauling created the scale that is used the most frequently. Caesium is a minor non-electrical substance with a value of 0.7, while fluorine is a very electronegative chemical with a value of 4.0.

Read more about Electronegativity.

List of the Top 5 Electropositive Elements

Cesium (Cs) is the element that the timeline is most picky about. Below is a list of the top five energy-related choices-

1. Cesium
2. Rubidium
3. Potassium
4. Sodium
5. Lithium

Also read- Father of Chemistry and F Block in Periodic Table.

Periodic Trends in the Electropositive Elements

The metallic nature of an element, its ionization energy, the distance between the nucleus and the valence shell, as well as the effective nuclear charge acting on the valence shell, are some of the variables that affect an element's electropositivity. The periodic trends in the elements' electronegativities are invariably the reverse of the periodic trends in their electropositivity. The electropositivity of the elements grows when traveling down a group, whereas the electronegativity of the elements drops while traversing down a group, while the electropositivity of the elements increases over a period. This explains why the elements at the bottom left of the periodic table are always electropositive, whereas those at the top right are the least electropositive. 

A metallic property called seropositivity is dependent on an element's metallic nature. The sole explanation for why all alkali metals are thought to be the most electropositive elements in the periodic table is this. The two most electropositive elements in the entire periodic table are cesium and francium. Fluorine, chlorine, and oxygen are the least electropositive elements in the periodic table because they have the highest electronegative values.  

Read more about the First 20 Elements of the Periodic Table, Nitride, and Variable Valency.

Electropositive Character of an Element

The electropositive quality of an element is defined as its capacity to liberate an electron from its outermost electron shell in order to generate a positively charged cation. The likelihood for one element to release an electron to another aspect is largest for elements with low energies. Several factors, including the propensity of an element to lose electrons, to push electrons toward another aspect, effectively capture the nature of electronegativity.  The periodicity of the element is listed below-

1. The electronegativity falls from top to bottom of the group as an element's atomic number lowers, increasing the atomic radius and the distance between the outermost electrons and the nucleus.
2. The periodic chart shows that the electropositivity decreases from left to right.
3. It takes less energy to accept an electron than to lose one when the outermost shell of an element is less than half full, but it is simpler to lose one when it is more than half full. 
4. From top to bottom in a group, the electron's electropositivity and metallic nature likewise rise. 

Application of Electropositive Elements:

Because of their distinct features and reactivity, electropositive elements are used in a wide range of scientific and technological domains. Some common uses are:  

1. Metallurgy: Electropositive elements are commonly utilized in metallurgical procedures to recover, refine, and alloy metals. For example, sodium and potassium are utilized as reducing agents to remove metals from their ores. 
2. Electrochemistry: Electropositive elements play an important role.

Read more about the Chemistry Periodic Table and Electronic Configuration of the First 30 Elements.

Points to Remember

1. Alkali metals and alkaline earth metals are the two groups of elements in the periodic table. 
2. Compared to the typical hydrogen electrode, which has a value of zero, the electrode potential of an electropositive element has a greater positivity.
3. Electropositive and electronegative are categories for both metals and nonmetals.
4. Metals and acidic hydrogen are examples of electropositive elements or groups that release their electrons.
5. There are both metals and non-metals.
6. Li+, Na+, and K+ are a few examples of monovalent alkali metals, whereas Be²+, Mg²+, and Ca²+ are examples of divalent alkaline earth metals.

Sample Questions for Electropositive Elements

Sample Question 1: Which element has the highest electropositivity? 

Solution: The element with the greatest electropositive character in the periodic table is calcium, symbol Ca. It is situated in the table's first group and sixth section. It possesses one electron in its outermost orbit, making it simple for it to transfer that electron in order to achieve the electrical configuration of the closest noble gas.

Sample Question 2: Why does potassium metal have a lower reactivity than sodium metal? 

Solution: The ionization enthalpy of sodium is 496 KJ mol, whereas the Hi of a potassium metal is 419 KJ mol-1. Therefore, we can conclude that potassium is more reactive than sodium because its Ionisation Enthalpy is lower.

Sample Question 3: What exactly are polyatomic ions? 

Solution: Polyatomic ions are ions that contain many atoms, either the same or different and act as a single unit of charge.

Sample Question 4: Why aren't lithium elements used in photoelectric cells instead of potassium and cesium metals? 

Solution: The elements with lower ionization enthalpies than lithium include potassium and calcium. Therefore, when exposed to light, these metals can emit electrons with ease. The usage of potassium and cesium in photoelectric cells is due to this.

Sample Question 5: Why does the group's electropositivity rise? 

Solution: The electronegativity drops as we move from top to bottom down the group because when an element's atomic number falls, the distance between its outermost electrons and its nucleus also reduces, as does the atomic radius.

Sample Question 6: Why do salts of lithium hydrate more often than those of any other alkali metal?

Solution: Compared to other alkali metal ions, lithium Li+ ions may more readily polarise water molecules due to their comparatively small size.