The Periodic Table: Metals, Nonmetals, and Metalloids

Using the periodic table, you can classify the elements in many ways. One useful way is by metals, nonmetals, and metalloids. The periodic table is organized in families and periods.


In the periodic table, you can see a stair-stepped line starting at Boron (B), atomic number 5, and going all the way down to Polonium (Po), atomic number 84. Except for Germanium (Ge) and Antimony (Sb), all the elements to the left of that line can be classified as metals.These metals have properties that you normally associate with the metals you encounter in everyday life.

  1. They are solid (with the exception of mercury, Hg, a liquid).
  2. They are shiny, good conductors of electricity and heat.
  3. They are ductile (they can be drawn into thin wires).
  4. They are malleable (they can be easily hammered into very thin sheets).

All these metals tend to lose electrons easily. The following figure shows the metals.



Except for the elements that border the stair-stepped line, the elements to the right of the line are classified as nonmetals (along with hydrogen). Nonmetals have properties opposite those of the metals.

The nonmetals are brittle, not malleable or ductile, poor conductors of both heat and electricity, and tend to gain electrons in chemical reactions. Some nonmetals are liquids. These elements are shown in the following figure.



The elements that border the stair-stepped line are classified as metalloids. The metalloids, or semi metals, have properties that are somewhat of a cross between metals and nonmetals.

Metalloids tend to be economically important because of their unique conductivity properties (they only partially conduct electricity), which make them valuable in the semiconductor and computer chip industry. The metalloids are shown in the following illustration.


The discussion over the study of the Periodic Table, the distribution of the elements on the basis Metals, Non-Metals and Metalloids and their General Properties is being discussed in the main article. In the below write up I’ve tried to give a detailed yet elementary look into the Periodic Table and their elements.

Brief history of Periodic Table:

The tabular arrangement of the elements according to their atomic numbers so that elements with similar properties are in the same column.

Now the question that arises here who holds the crown to the emergence of Idea of arrangements of these elements?
In the history of the periodic table, Döbereiner’s triads were an early attempt to sort the elements into some logical order by their physical properties, that was reported in the 1817. After that Newland’s Law of Octave became the heir of the arrangements of elements according to their increasing atomic masses and repeated properties of every 8th element, in year 1865. This title of the most appropriate arrangements of the elements was about to be crowned to Lother Meyer’s Classification but Mendeleev’s Periodic Law that “properties of the elements are the periodic function of their atomic masses” laid its hold on it which was presented in th esame year as of Lother Meyer’s Classification in year 1869. To this date the extensively accepted Periodic table is Modern Periodic Table that is formulated as “ The properties of elements are the peiodic functions of their atomic numbers.” Which was presented by Mosley in 1913 as it encountered most of the objections that were reported in the Mendeleev’s Classification.

Why do we need Periodic Table?

To summarize, the periodic table is important because it is organized to provide a great deal of information about elements and how they relate to one another in one easy-to-use reference. The table can be used to predict the properties of elements, even those that have not yet been discovered.


  • On elementary level concept of Metals, Non-Metals and Metalloids are introduced to the learner’s understanding so that their cognition is built to the level that they can learn about the further description of the Periodic Table.
  • Lavoiser, another name in the classification of elements of periodic table as Metals, Non-Metals and Metalloids.

Defining Metals:

Elements having any of various opaque (through which light cannot pass), fusible (those which can be liquefied by heat), ductile (one that can undergo significant deformation before failure), and typically lustrous (shiny) substances that are good conductors of electricity and heat, form cations (positive ions) by loss of electrons, and yield basic oxides and hydroxides. Metals are solids at room temperature with the exception of mercury, which is liquid at room temperature (Gallium is liquid on hot days).

As the definition itself has defined the Physical properties of the Metals so we’ll discuss the Chemical properties of the Metals.

Chemical Properties:

  1. Metals when burned in the presence of oxygen, they combine with oxygen to form metallic oxides which are basic in nature.

    Metal + Oxygen (from air) à Metal Oxide

    For example

    2 Mg + O2 à 2 MgO (Magnesium Oxide)

  2. Metal hydroxide changes red litmus blue which shows its basic characteristics.

  3. Most metals corrode when they are exposed to atmosphere. For example, the iron gets rusty after sometime if it is not painted. Titanium is highly resistant to corrosion.

  4. Different metals react differently with water. Sodium reacts violently with water forming sodium hydroxide and hydrogran. Magnesium reacts mildly with water but vigorously with steam.

  5. Generally, metals are in a solid state at room temperature.

  6. Since the metals are further to the left on the periodic table, they have low ionization energies and low electron affinities, so they lose electrons relatively easily and gain them with difficulty. They also have relatively few valence electrons, and can form ions (and thereby satisfy the octet rule) more easily by losing their valence electrons to form positively charged cations .

Defining Non-Metals:

They are elements or substances that are not a metal. The one’s who are lacking the properties of the metals. Nonmetals are (usually) poor conductors of heat and electricity, and are not malleable or ductile; many of the elemental nonmetals are gases at room temperature, while others are liquids and others are solids.

As the definition itself has defined the Physical properties of the Non-Metals so we’ll discuss the Chemical properties of the Non-Metals.

Chemical Properties:

  1. When nonmetals combine with other nonmetals, they tend to share electrons in covalent bonds instead of forming ions, resulting in the formation of neutral molecules.
  2. They form acidic oxides.
  3. They are good oxidizing agents.
  4. Reaction of non-metals with water: They do not react with water (steam) to evolve hydrogen gas.
  5. Reaction of non-metal with acids: They do not react with acids because they are negative charged electron.
  6. Nonmetals are further to the right on the periodic table, and have high ionization energies and high electron affinities, so they gain electrons relatively easily, and lose them with difficulty. They also have a larger number of valence electrons, and are already close to having a complete octet of eight electrons. The nonmetals gain electrons until they have the same number of electrons as the nearest noble gas (Group 8A), forming negatively charged anions.

Defining Metalloids:

They are elements intermediate in properties between the typical metals and nonmetals, a nonmetal is that can combine with a metal to form an alloy. Metalloids can also be called semimetals. Elements: Silicon; Boron; Arsenic; Antimony. Physically, they are shiny, brittle solids with intermediate to relatively good electrical conductivity and the electronic band structure of a semimetal or semiconductor.

As the definition itself has defined the Physical properties of the Metalloids so we’ll discuss the Chemical properties of the Metalloids.

Chemical Properties:

  1. Metalloids are good semiconductors.

  2. The reactivity of metalloids are dependent on the properties of elements they are reacting with.

  3. Electronegativity and ionization energy are between metals and non-metals.

  4. Oxidation: They are capable of forming Glasses.

  5. These semiconductors are extremely important in computers and other electronic devices.

  6. Few metalloids contract when they are heated.


To sum up, the periodic table of elements is an extremely important tool that is a fundamental piece in any laboratory, classroom, or hospital. The periodic table has an endless array of benefits; it allows one to easily find an element, predict their properties even before their discoveries. It works somewhat like what we call Lesson Plan, or the way you organize your day or let’s call it the Timetable of Elements.