Periodic Table of Elements

The Periodic table of elements is a systematic arrangement of 118 known chemical elements. These chemical elements are organized in order of increasing atomic number. The horizontal rows from left to right are called periods while the vertical columns from top to bottom are called groups in a periodic table.

What is Periodic Table ?

A periodic table is a tabular representation in which all the known chemical elements are arranged in horizontal rows called periods and vertical columns called groups based on their atomic number and atomic structure respectively.

It is an arrangement of all the known elements and therefore provides information about the elements such as their mass, electron number, electron configuration, and their unique chemical properties. 

List of Periodic Table Elements

Here is the table representing 118 elements of the periodic table. The elements listed are arranged according to the increasing order of atomic number and their respective atomic weight, symbol, density, and electronegativity.

Elements in Periodic Table with Atomic Mass
Atomic Number	Chemical Element Name	Symbol	Atomic Mass (amu)	Density (g/cm3)	Electronegativity
1	Hydrogen	H	1.0079	0.00008988	2.2
2	Helium	He	4.0026	0.0001785	–
3	Lithium	Li	6.941	0.534	0.98
4	Beryllium	Be	9.0122	1.85	1.57
5	Boron	B	10.811	2.34	2.04
6	Carbon	C	12.0107	2.267	2.55
7	Nitrogen	N	14.0067	0.0012506	3.04
8	Oxygen	O	15.9994	0.001429	3.44
9	Fluorine	F	18.9984	0.001696	3.98
10	Neon	Ne	20.1797	0.0009002	–
11	Sodium	Na	22.9897	0.968	0.93
12	Magnesium	Mg	24.305	1.738	1.31
13	Aluminum	Al	26.9815	2.7	1.61
14	Silicon	Si	28.0855	2.329	1.9
15	Phosphorus	P	30.9738	1.823	2.19
16	Sulfur	S	32.065	2.07	2.58
17	Chlorine	Cl	35.453	0.0032	3.16
18	Argon	Ar	39.948	0.001784	–
19	Potassium	K	39.0983	0.89	0.82
20	Calcium	Ca	40.078	1.55	1
21	Scandium	Sc	44.9559	2.985	1.36
22	Titanium	Ti	47.867	4.506	1.54
23	Vanadium	V	50.9415	6.11	1.63
24	Chromium	Cr	51.9961	7.15	1.66
25	Manganese	Mn	54.938	7.21	1.55
26	Iron	Fe	55.845	7.874	1.83
27	Cobalt	Co	58.9332	8.9	1.88
28	Nickel	Ni	58.6934	8.908	1.91
29	Copper	Cu	63.546	1.9	60
30	Zinc	Zn	65.39	1.65	70
31	Gallium	Ga	69.723	1.81	19
32	Germanium	Ge	72.64	2.01	1.5
33	Arsenic	As	74.9216	2.18	1.8
34	Selenium	Se	78.96	2.55	0.05
35	Bromine	Br	79.904	2.96	2.4
36	Krypton	Kr	83.798	3	1×10−4
37	Rubidium	Rb	85.4678	0.82	90
38	Strontium	Sr	87.62	0.95	370
39	Yttrium	Y	88.906	1.22	33
40	Zirconium	Zr	91.224	1.33	165
41	Niobium	Nb	92.906	1.6	20
42	Molybdenum	Mo	95.94	2.16	1.2
43	Technetium	Tc	98	1.9	~ 3×10−9
44	Ruthenium	Ru	101.07	2.2	0.001
45	Rhodium	Rh	102.91	2.28	0.001
46	Palladium	Pd	106.42	2.2	0.015
47	Silver	Ag	107.87	1.93	0.075
48	Cadmium	Cd	112.411	1.69	0.159
49	Indium	In	114.82	1.78	0.25
50	Tin	Sn	118.71	1.96	2.3
51	Antimony	Sb	121.76	2.05	0.2
52	Tellurium	Te	127.6	2.1	0.001
53	Iodine	I	126.9045	2.66	0.45
54	Xenon	Xe	131.293	2.6	3×10−5
55	Cesium	Cs	132.91	0.79	3
56	Barium	Ba	137.327	0.89	425
57	Lanthanum	La	138.91	1.1	39
58	Cerium	Ce	140.12	1.12	66.5
59	Praseodymium	Pr	140.9077	1.13	9.2
60	Neodymium	Nd	144.24	1.14	41.5
61	Promethium	Pm	145	1.13	2×10−19
62	Samarium	Sm	150.36	1.17	7.05
63	Europium	Eu	151.964	1.2	2
64	Gadolinium	Gd	157.25	1.2	6.2
65	Terbium	Tb	158.9253	1.2	1.2
66	Dysprosium	Dy	162.5	1.22	5.2
67	Holmium	Ho	164.9303	1.23	1.3
68	Erbium	Er	167.259	1.24	3.5
69	Thulium	Tm	168.9342	1.25	0.52
70	Ytterbium	Yb	173.04	1.1	3.2
71	Lutetium	Lu	174.967	1.27	0.8
72	Hafnium	Hf	178.49	1.3	3
73	Tantalum	Ta	180.9479	1.5	2
74	Tungsten	W	183.84	2.36	1.3
75	Rhenium	Re	186.207	1.9	7×10−4
76	Osmium	Os	190.23	2.2	0.002
77	Iridium	Ir	192.22	2.2	0.001
78	Platinum	Pt	195.08	2.28	0.005
79	Gold	Au	196.97	2.54	0.004
80	Mercury	Hg	200.59	2	0.085
81	Thallium	Tl	204.3833	1.62	0.85
82	Lead	Pb	207.2	1.87 (2+) 2.33 (4+)	14
83	Bismuth	Bi	208.9804	2.02	0.009
84	Polonium	Po	209	2	2×10−10
85	Astatine	At	210	2.2	3×10−20
86	Radon	Rn	222	2.2	4×10−13
87	Francium	Fr	223	>0.79[6]	~ 1×10−18
88	Radium	Ra	226	0.9	9×10−7
89	Actinium	Ac	227	1.1	5.5×10−10
90	Thorium	Th	232.0381	1.3	9.6
91	Protactinium	Pa	231.0359	1.5	1.4×10−6
92	Uranium	U	238.0289	1.38	2.7
93	Neptunium	Np	237	1.36	≤ 3×10−12
94	Plutonium	Pu	244	1.28	≤ 3×10−11
95	Americium	Am	243	1.13	–
96	Curium	Cm	247	1.28	–
97	Berkelium	Bk	247	1.3	–
98	Californium	Cf	251	1.3	–
99	Einsteinium	Es	252	1.3	–
100	Fermium	Fm	257	1.3	–
101	Mendelevium	Md	258	1.3	–
102	Nobelium	No	259	1.3	–
103	Lawrencium	Lr	262	1.3	–
104	Rutherfordium	Rf	267	–	–
105	Dubnium	Db	268	–	–
106	Seaborgium	Sg	269	–	–
107	Bohrium	Bh	270	–	–
108	Hassium	Hs	269	–	–
109	Meitnerium	Mt	277	–	–
110	Darmstadtium	Ds	281	–	–
111	Roentgenium	Rg	282	–	–
112	Copernicium	Cn	285	–	–
113	Nihonium	Nh	286	–	–
114	Flerovium	Fl	290	–	–
115	Moscovium	Mc	290	–	–
116	Livermorium	Lv	293	–	–
117	Tennessine	Ts	294	–	–
118	Oganesson	Og	294	–	–

Important Terms in Periodic Table

Terms	Description
Atomic Number	The number of protons that constitutes an element’s nucleus is called its Atomic Number (Z). e.g. Carbon contains 6 protons then, so its atomic number must be 6 only.
Atomic Mass	It is defined as the average mass of the atoms of an element. It is measured on the basis of the relative natural abundance of the isotopes of the element. Atomic mass is also termed Atomic Weight (A). It is measured in the atomic mass unit (amu).
Period	The horizontal rows from left to right in a periodic table are called Periods. There are a total of 7 periods in the periodic table. The elements are arranged horizontally due to their similarities in properties, like the same atomic orbitals and so on.
Group	The vertical columns from top to bottom in a periodic table are called Groups. There is a total of 18 groups in the periodic table. The elements are arranged vertically due to their similarities in properties, as they have the same number of valence electrons in them.
Symbol of an Element	A symbol is a notion that is used to represent a chemical element using a letter or a combination of two to three letters. e.g. The chemical symbol of Carbon is C, while Fe is used for Iron and so on.

Classification of Elements in Periodic Table

The 118 elements are arranged in 7 periods and 18 groups as shown above. Further, the elements are divided into different blocks.

Block	Elements Included	Last Electron Subshell Filled
s-block	Group 1 (Alkali Metals)	s-subshell
	Group 2 (Alkaline Earth Metals)
p-block	Group 13 (Boron Family)	p-subshell
	Group 14 (Carbon Family)
	Group 15 (Nitrogen Family)
	Group 16 (Oxygen Family)
	Group 17 (Fluorine Family)
d-block	Groups 3 to 12 (Transition Elements)	d-subshell
f-block	Lanthanides (Rare Earth Elements)	f-subshell
	Actinides

Mendeleev Periodic Table

In order to represent similarities and trends in the behavior of elements, Mendeleev developed the periodic table, which is an arrangement of elements in an increasing atomic mass order in tabular form.

According to Mendeleev’s Periodic Table, elements were arranged as per their fundamental property, atomic mass, and chemical characteristics. Only 63 elements were known at the time of Mendeleev’s work. In the Mendeleev periodic table, the horizontal row and vertical columns were referred to as groups and periods, respectively. 

However, Mendeleev’s Periodic Table fails due to many flaws in it. Some of them are, that it failed to designate Hydrogen and Noble gases in it. Also, the increasing order of the atomic mass of the elements wasn’t regular throughout the table. Even, the discovery of isotopes violates the Mendeleev Periodic Law.

Read More:

• Modern Periodic Table
• Mendeleev periodic table
• Modern Periodic Law
• History of Periodic Table
• Atomic Structure

FAQs on Periodic Table of Elements

What is Periodic Table of Elements?

The Periodic Table of Elements is a tabular arrangement of chemical elements organized by their atomic number, electron configuration, and recurring chemical properties. The table is divided into rows called periods and columns called groups or families.

Who Discovered Periodic Table of Elements?

The Periodic Table of Elements was not discovered by a single person, but its development is credited to Dmitri Mendeleev, a Russian chemist, who arranged elements based on their properties in 1869.

Who Made the Modern Periodic Table?

In 1913, Henry Moseley introduced an updated version of the periodic table, commonly referred to as “The Modern Periodic Table.”

How is the Periodic Table Arranged?

The Periodic Table is arranged in order of increasing atomic number, with elements grouped together based on similar chemical properties and arranged into periods (rows) and groups (columns).

What is Atomic Number?

The number of protons that constitutes an element’s nucleus is called its Atomic Number (Z). e.g. Carbon contains 6 protons then, its atomic number must be 6 only. 

Can two different elements have the same atomic number?

The number of neutrons in an atom from two different elements can be similar, but the number of protons will never be same. Each element has a specific number of protons, which corresponds to the number of atoms.

How To Calculate Atomic Mass?

The atomic mass can be calculated by adding the mass of protons and neutrons in an element. 

What is a Group in Periodic Table?

The Column in the periodic table refers to the group of the periodic table. The elements of the same group have similar physical and chemical properties.