Diagonal Relationships

What is a Diagonal Relationship in the Periodic Table?

According to their position, some elements in the periodic table connect on an adjacent basis. The modern periodic table has the positioning criteria according to the element’s atomic number. The second and third row of the periodic table has the placement of elements with diagonal relationships. In a general notice, these elements are present among the first twenty elements of the periodic table.

The diagonal elements in the periodic table represent similarities among the elements and move from the left towards the right. They are the key members of lightweight elements in the periodic table. The pairs that show the diagonal relationship in the periodic table are –

• Lithium (Li) from group IA and Magnesium from group IIA
• Beryllium (Be) from group IIA and Aluminum from Group IIIA
• Boron (B) from group IIIA and Silicon from group IVA
• Carbon (C) from group IVA and Phosphorus from group VA

Reason for Diagonal Relationships

The existence of a diagonal relationship varies due to many properties. When two elements in the periodic table with different properties move down the groups and across the table match with such adjacent relationships, each element in the periodic table has a certain polarizing power of its own. When these elements move diagonally in the periodic table, there is a noticeable increment in the polarizing power.

Whenever the polarizing power of an element increases, the charge in its ions gets extra power. The ion size of ions decreases when the charge within the ions increases. When these ions move downwards due to a decrease in polarizing power, the size of the ions also decreases. Hence, the major reason to place it with a diagonal relationship is to avoid such fluctuation in charge.

Hence to maintain the proper balance in the ionic size charge and radius of the ions, the diagonal relationships are present in the periodic table. This also helps the elements function according to their characteristics with complete performance. The placement of elements in the adjacent position matches their power and charge present in it. This affects their functioning and stability in a very positive manner. To define diagonal relationships, it is necessary to know about the properties and reactive states of the elements in that position.

Diagonal Relationship between Lithium and Magnesium

Lithium (Li) and Magnesium (Mg) are the two important elements from different groups in the periodic table. These elements are the first diagonal pair that balances each other’s properties to avoid clash and fluctuation. The relationship depends upon various reasons and values:

• Melting point: All the alkali metals have proper balance in melting points. But Lithium (Li) in group IA and Magnesium (Mg) in group IIA have comparatively higher melting points. But when they are in a diagonal relationship, both manage to balance their high melting points and react with stable value and frequency.
• The solid form of bicarbonates: Lithium (Li) does not have the property to form bicarbonate. Magnesium (Mg), when forming a combination with sodium, forms solid NAHCO3.
• Decomposing quality: Lithium (Li) and Magnesium (Mg) are the first pair in a diagonal relationship in the periodic table. There is a noticeable variation in the decomposing quality of both elements. While all the Lithium compounds get into the decomposition process after heating, the Magnesium (Mg) compounds have the corresponding qualities.
• Solubility: Almost all Lithium (Li) compounds lack solubility except LiOH, which is partially soluble in water. Apart from this, all the Magnesium (Mg) salts have great soluble points in this case. The diagonal relationship between these two elements manages the property of solubility and helps in reactive stages.

Similarities

Apart from the various imbalance between Lithium (Li) and Magnesium (Mg) which places them in a position with a diagonal relationship. Certain similarities may be the result of the relationship and the balance which tends to grow by the adjacent positions:

• The electronegativity values of Lithium (Li) and Magnesium (Mg) are almost equal.
• When reacting with chloride compounds, both the elements convert themselves from aqueous hydrate to crystallize and deliquescent texture. The resulting chlorides are easily soluble in ethanol.
• Both elements’ characteristics are covalent and thus define a diagonal relationship by their balance with other elements in the periodic table.
• The hydroxides of Lithium (Li) and Magnesium (Mg) have weak bases, and as a result, they easily move towards the decomposing state whenever they go through the heat.
• The carbonates, hydroxides, fluorides, and phosphates comprise the thriftily soluble with water.
• Compared to other elements in their respective groups, Lithium (Li) and Magnesium (Mg) are comparatively harder and lighter.

Change in Properties of Compounds after Diagonal Relationship

• All the metals which form a diagonal relationship from each group have distinct properties, and after the adjacent position, certain changes are noticeable.
• The element reacts friendly with oxygen to form oxides and peroxides.
• Nitrides formations also occur with stabilizing values and temperatures.
• Solvent properties increase mutually after the diagonal relationship.
• Mutual reactions of alkali metals come to a stable state of charge density by gaining and losing a cation (+ve ion) and anion (-ve ion) under room temperature.

The basic study of chemistry begins with the periodic tables. The elements in the periodic table and their position are the basis of chemistry in all aspects. In the modern periodic table, elements get their placement according to their atomic number and chemical properties. The atomic number affects the periodic functioning of an element by its chemical properties.

The diagonal relationship of elements has a positive effect on the nature of the elements. The reactivity and changing property get and balance in state and due to which the formation of other elements becomes easy. There are certain elements in the periodic table that have identical properties. The placement of these elements in the modern periodic table is adjacent. Therefore these elements are in diagonal relationships with each other.