Periodic Table: The Basics of Chemistry

Avatar of Miral Nassar
Updated on: Educator Review By: Michelle Connolly

A list of the elements may be found in the periodic table. The table lists the elements according to the atomic structure of each one. This applies to both the number of protons and electrons in their outer shell. The elements are listed according to their atomic number, or the number of protons in each atom, from left to right and top to bottom.

Why is it referred to as a Periodic Table?

It is named “periodic” because the components are arranged in cycles or periods. Depending on their atomic number, elements are arranged in rows from left to right (the number of protons in their nucleus). Specific columns are skipped for elements with the same valence electrons to align on the same columns. When arranged in this manner, the components in the columns have many characteristics.

The table’s horizontal rows are separated by periods. There are seven (or eight) total periods. The first is brief and only contains hydrogen and helium. There are 32 components in the sixth period. The leftmost element in each period has one electron in its outer shell, whereas the rightmost element has a complete shell.

The columns of the periodic table are groups. There are 18 columns or groups, and the attributes of the various groupings vary.

Noble or inert gases are one type of group. The periodic table’s 8th or last column contains all of these elements. They are all extremely stable because they each have a complete outer shell of electrons (they tend not to react with other elements). The alkali metals, arranged on the leftmost column, provide another illustration. They are all incredibly reactive and contain only one electron in their outer shell, which makes them all quite similar. 

Chemists find it easier to deal with elements when related elements are lined up and grouped. This is because they can comprehend and foresee how an element will function or respond in a particular circumstance.

In the periodic table, each element has a unique name and abbreviation. Some abbreviations, like H for hydrogen, are simple to recall. Some are a little tougher, like Fe for iron or Au for gold. The letter “Au” in gold derives from the Latin word for gold, aurum.

Periodic Table Facts for Kids

Who created it?

Dmitri Mendeleev, a Russian scientist, proposed the periodic table in 1869. Mendeleev could precisely forecast the characteristics of numerous elements using the table before they were found.

Interesting Facts about the Periodic Table

  • The ability of carbon to generate up to 10 million distinct compounds makes it unique. For life to exist, carbon is crucial.
  • The rarest element on Earth is francium. Only a few ounces of it are present on Earth at any moment.
  • Helium is present on Earth, although it was initially found by studying the sun.
periodic table

Some of the Chemical Series of the Periodic Table

Alkali Metals

The chemical elements that comprise group 1 of the periodic table are known as alkali metals. They exhibit a red colour when they are pure, rigid, and only have one valence electron. They like performing reactions in which they lose this twin electron and gain a positive charge. They must be preserved in oil because of their severe reaction to water. Since they are unstable and react quickly to other elements, they are only found in nature with help. Except for noble gases, they form strong bonds with all other elements. They immediately become black while they are in the air.

Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), caesium (often spelt cesium) (Cs), and francium are alkali metals (Fr). The least reactive is lithium. While francium is highly uncommon, it was previously believed to be the most reactive element. Nevertheless, more recently, it was anticipated that caesium is more reactive than francium because of relativity.

The most significant alkali metal is sodium. Sodium chloride, or table salt or NaCl, is one of the most considerable sodium salts. Furthermore, sodium hydroxide (NaOH), popularly known as “caustic soda,” is created. 

Alkaline Earths

The second category of metals on the periodic table are the alkaline earth metals. They are linked to alkali metals, but because it takes more energy to remove their two electrons, they do not react as much and may thus be held in gasoline. They have a +2a charge as ions. The alkaline earth metals are primarily silver-coloured, soft metals that react quickly with halogens and water to generate salts, but not as quickly as some alkali metals to form alkaline hydroxides. These metals’ crusts contain a large number of prokatates and hantates.

Beryllium, magnesium, calcium, strontium, barium, and radium are alkaline earth metals. Radium has high radioactivity.


A lanthanide is one of a set of 15 elements with atomic numbers ranging from 57 to 71. This is sometimes referred to as the lanthanide series or the lanthanoid series. This group’s lanthanum starting point and lutetium ending point are both on the periodic table. Except for lutetium, which is a d-block lanthanoid, all lanthanoids are f-block elements, meaning that electrons occupy the 4f electron shell. From lanthanum, the lanthanoid series (Ln) is called.

Lanthanides are metals that act similarly to one another. When submerged in water, most of them, like alkali metals, progressively transform into their hydroxides. Like other metals, they often develop an oxide layer when exposed to air.

Rare earth elements include Lanthanides, Scandium, and Yttrium. All lanthanoids are soft, silvery metals that fade quickly in the air. With an increase in atomic number, the hardness rises.

Just a small number of lanthanides are mined since they are rare. However, some are used in various applications, including magnets, superconductors, chemical catalysts, and optical devices like lasers.


The 15 chemical elements of the actinide series are located on the periodic table between actinium and lawrencium. Their atomic weights range from 89 to 103. Actinium serves as the inspiration for the actinide series. The elements are all radioactive. The most frequent naturally occurring actinide is thorium, followed by uranium.

Transition Metals

The middle of the periodic table contains a group of transition metals. On the left are the boron group elements, starting with beryllium, and to the right are the alkaline earth metals. In 1921, the phrase “transition element” was introduced for them.

These metals have atomic numbers ranging from 21 to 30, 39 to 48, 57 to 72 to 80, 89 to 104 to 112. In the transition series of elements, several elements, including Zn, Cd, Hg, La, and Ac, have highly contentious positions. The lanthanide series and the actinide series, respectively, also include La and Ac.

Transition metals exhibit many general characteristics. For example, compared to alkaline earth metals, they are more rigid and less reactive.

Moreover, they are more durable than post-transition metals. With the help of other elements, they create vibrant chemical compounds. The majority of them have many oxidation states. They are electrical conductors, much like other metals.

Iron, zinc, and chromium are a few of the transition metals that are essential for human health. Cadmium and mercury are two transition metal elements that can harm the body. Some elements, such as gold or silver, have no negative effects on us. Transition metals are the most prevalent compared to other groups on the periodic table.

A few of the transition metals are coloured; the majority are silver-grey or silver-bluish.

Metalloids/Semi metals/Half metals

A chemical element is a semimetal or a metalloid. Elements known as metalloids combine the characteristics of both metal and nonmetal elements. While dazzling, it is fragile. Although tedious, it conducts electricity.

Silicon is the most popular semimetal. Between metals and nonmetals, silicon exhibits electrical conductivity. It is a semiconductor.

A rough classification of metalloids may be made by consulting the periodic table of elements. Notice the double diagonal line: top left Boron and Aluminum, bottom right Polonium and Astatine. The metalloids are those diagonals. Certain semimetals are not metalloids, while some metalloids are not semimetals.


A chemical element that lacks the characteristics of a metal is referred to as nonmetal or nonmetal. These might be gases or elements without the characteristics of metals. Examples of gaseous elements include, but are not limited to, hydrogen, helium, oxygen, nitrogen, fluorine, neon, or radon. Sulfur is an illustration of a solid that is a nonmetal. It is yellow and not at all glossy. Bromine is an illustration of a liquid nonmetal. It’s red. A nonmetal can be an effective insulator of heat and cold. Typically, nonmetals include gases and fragile solids. For example, a periodic table element can be categorised as a metal, a semimetal, or a nonmetal.

There are five times as many metals as nonmetals in the periodic table. One of the nonmetals, oxygen, makes up over Half of the Earth’s crust, seas, and atmosphere. Two nonmetals, hydrogen and helium, account for over 99 percent of the visible Universe. Moreover, nonmetals make up practically all living things, and they may combine to generate a much wider variety of combinations than metals.


The halogens are chemical elements in Group 17 or the second-to-right column of the periodic table. Fluorine, chlorine, bromine, iodine, astatine, and ununseptium are the elements in the group. Halogen is frequently referred to as “salt producer,” even though its literal meaning is “salt becomer.” Due to their high reactivity, they are likely to combine to form compounds with other elements on the left side of the periodic table. This is because they lack one electron. Except for astatine, which is not found in nature, they are hardly ever discovered by itself. Iodine is the least reactive element, whereas fluorine is the most reactive. Astatine is rare and highly radioactive.

Noble Gases

A set of elements that are all gases is known as noble gases. Group 18 of the periodic table contains all of these elements. Each molecule is a single atom since they are all monoatomic. They seldom ever respond to other factors. This is because their outer electron shell contains all eight electrons. There are six noble gases helium, neon, argon, krypton, xenon and radon.

Why not subscribe to our LearningMole Library for as little as £1.99 per month to access over 1500 fun educational videos.

Leave a Reply

Your email address will not be published. Required fields are marked *