Periodic Table

How is the periodic table of the elements arranged?

The periodic table is an organized arrangement of the chemical elements, in order of their atomic number (number of protons), electron configurations, and their chemical properties. This ordering segregates elements according to their periodic trends that are elements with similar behavior in the same column.

Naming

All elements are shown by a square on the Periodic Table of Elements and each of them is marked by its own series of letters.   Carbon is C, Calcium is Ca, and Hydrogen is H.

The elements are given in increasing order of the atomic number. And every square has the elements’ atomic number and atomic mass.

The atomic number means the number of protons in the nucleus or the electrons orbiting the nucleus. That is number of protons= number of electrons orbiting the nucleus of an atom = atomic number.

The atomic mass is the average mass of the protons, electrons and neutrons in a single atom.

An atom of carbon with protons and neutrons (nucleus) in the centre and electrons orbiting.

Periods

Periods are the horizontal rows on the periodic chart.   Every element in a period has the same number of electron orbits. 7 is the maximum no. of orbits which an element has according to the discovered elements by the scientists.

The periodic chart has 7 periods.   Elements like Hydrogen and Helium are in Period 1- which means they have one orbit of the electron.  Elements such as Sodium and Magnesium, Aluminum, are in Period 3- meaning they have three electron orbits.

Other Useful Aspects 

 Credit: https://in.pinterest.com/pin/573646071271981135/

Some interesting glance at the periodic table

Check Point 

A. Fill in the blanks :

1. The periodic tableis an organized arrangement of the chemical elements, in order of their ………………….. ……….. (number of protons), electron configurations, and their chemical
2. The ……… …………….. represents the number of protons in the nucleus or the electrons orbiting the nucleus.
3. The…………… ………..… is the average mass of the protons, electrons and neutrons in a single atom.
4. …………… are noted by the vertical column and represent families of elements.
5. Periods are noted by the …………………. rows on the periodic chart. 

B. State True or False

1. Each compound is represented by a square on the Periodic Table and each is denoted by its own unique series of letters.
2. Groups are the horizontal rows and represent families of elements.
3. While groups and periods are useful in understanding the chemical families, elements are also seen as being organized by blocks.
4. The noble gases have low melting and boiling points.
5. Over time a color scheme has been added to the periodic chart to help understand which elements belong to named categories.

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