How Many Periods Are In The Periodic Table?

How many periods are in the periodic table?

What Are Periods & Groups In The Periodic Table?

The periodic table is a hugely important tool in chemistry.

It organizes all of the elements according to their properties and makes it easy for chemists to find the information they need. But how many “periods” are in the periodic table?

How Many Periods Are In The Periodic Table

There are seven periods in the periodic table.

A period is a horizontal row of elements, and each period contains two new elements (atoms with different numbers of protons in their nucleus).

The first period has only one element (hydrogen), and the last period has six elements (including the heavy metal platinum).

How many periods are in the periodic table?

There are seven periods in the periodic table, and each one contains elements with similar properties.

Explain It To A Child

The periodic table has seven periods. A period is a row of elements with two new elements in each period.

The first period contains only two elements, hydrogen, and helium. The second period contains eight elements, including lithium, sodium, and potassium. The third period contains 18 elements, including calcium, magnesium, and aluminum.

As you move down the periodic table, the elements become increasingly complex. The seventh period, which is currently incomplete, contains 32 elements.

These include plutonium, uranium, and neptunium. Scientists are still working to discover new elements, so it’s possible that the periodic table will one day have more than seven periods.

How periods on the periodic table are arranged

The periodic table is organized into seven periods. The first period contains two elements, hydrogen, and helium. The second period contains eight elements, including lithium, beryllium, and boron.

There are seven periods in the periodic table

The third period contains 18 elements, including carbon, nitrogen, and oxygen. The fourth period contains 32 elements, including silicon, sulfur, and chlorine.

The fifth period contains 30 elements, including phosphorus, arsenic, and antimony. The sixth period contains 38 elements, including sulfur, selenium, and tellurium.

Finally, the seventh period contains 18 elements, including uranium, neptunium, and plutonium.

What are the 7 periods in the periodic table?

The periodic table is arranged into seven periods, each period containing elements with progressively higher atomic numbers.

The periodic table is organized into seven periods.
The first period contains elements with atomic numbers 1 through 18, while the second period contains elements with atomic numbers 19 through 36.

The remaining five periods contain elements with atomic numbers 37 through 54, 55 through 72, 73 through 90, 91 through 108, and 109 through 126.

All of the elements in a given period have similar chemical properties due to their having the same number of Electrons in their outermost orbital.

As one moves from left to right across a period, the elements become increasingly reactive due to the increasing number of valence electrons.

The increased reactivity results in a change in the way that the element interacts with other atoms and molecules.

As one moves down a group within a period, the elements become less reactive due to the increase in the size of their atom’s nucleus.

The increased size makes it more difficult for the valence electrons to interact with other atoms and molecules.

  • The first two periods of the periodic table are considered to be part of the s-block because they contain only s-orbital electrons.
  • The third through seventh periods are considered to be part of the p-block because they contain p-orbital electrons.
  • Finally, the eighth period contains both s- and p-orbital electrons and is thus referred to as the d-block. 

All of the periods are further divided into groups, with each group containing elements with similar chemical properties.

There are 18 groups in all, which are labeled numerically (1 through 18) or by letter (A through G). 

Elements in Groups 1 and 2 are known as metals, while those in Groups 13 through 18 are known as nonmetals.

Metalloids occupy the space between metals and nonmetals on the periodic table and include elements such as:

  • silicon
  • boron
  • arsenic
  • tellurium

Finally, Noble gases are found in Group 18 and include:

  • helium
  • neon
  • argon
  • krypton
  • xenon
  • radon

These gases are odorless, colorless, and nonreactive under most conditions. 

Each element has unique chemical properties that arise from its particular arrangement of electrons.

By understanding these properties, chemists can predict how an element will interact with other substances and can develop new applications for these interactions.

In this way, the periodic table serves as a valuable tool for scientists across a variety of disciplines.

How the first period to the seventh period in the periodic table works

The periodic table is arranged into seven periods, each period containing elements with progressively higher atomic numbers

The periodic table is a chart that shows how the elements are related to one another.

The elements are arranged in order of increasing atomic number, which is the number of protons in an element’s nucleus.

The first period contains elements with atomic numbers 1-18. The second period contains elements with atomic numbers 19-36, and so on. The seventh period contains elements with atomic numbers 103-118.

Each element has unique properties that are determined by its atomic number. For example, hydrogen (atomic number 1) is a gas, while oxygen (atomic number 8) is solid.

The elements in the first period all have similar properties because they have similar atomic numbers. The first 18 elements are all metals, and they are all fairly reactive

They are also all lustrous, meaning they reflect light well. As you move down the periodic table, the elements become less reactive and denser.

The seventh period contains the noble gases, which are all very unreactive and non-metallic. They are also all odorless and colorless.

The elements in the periodic table are arranged in such a way that they can be predicted based on their atomic number. This knowledge can be used to understand the physical and chemical properties of new elements as they are discovered.

What are the properties of the periods on the periodic table?

The properties of the periods on the periodic table are determined by the number of protons in the nucleus of an atom.

The first period consists of elements with one to two protons in their nucleus, while the second period contains elements with three to 10 protons.

The properties of elements become increasingly metallic moving down a period from top to bottom.

This is due to the increasing number of electrons in the outermost orbital, which makes it easier for these electrons to be lost.

As a result, elements in the lower periods are generally more reactive than those in the upper periods.

The properties of elements also vary widely within a period, with those in the middle generally being more metallic than those at the extremes.

For example, sulfur is a non-metal, while chromium is a metal. This variation is due to the different number of electrons in the outermost orbital.

Elements with eight electrons in this orbital are called noble gases and are relatively unreactive. This group includes helium, neon, argon, and xenon.


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Author

  • Keith Chen - Jacks of Science Writer

    Keith Chen is Jacks of Science Senior Staff Writer and authority on chemistry and all things science. He is currently a full-time scientific analyst focused on chemical engineering, organic chemistry, and biochemistry. Keith has held roles such as chemist, engineer, and chief technician. His degree is focused around Physical chemistry and Analytical chemistry, but his passion is biomedical. He completed an internship at the All-Hands-Chemistry Discovery Center and Scientific Exploration Lab in Chicago. In his free time, he enjoys studying Zoology as a passion project.