The periodic table is a tabular arrangement of chemical elements, ordered by their atomic number, electron configuration, and recurring chemical properties. The elements are listed in rows to illustrate periodic trends, with columns grouping elements with similar characteristics.

आवर्त सारणी एक ऐसी तालिका है जिसमें रासायनिक तत्वों को उनके परमाणु क्रमांक, इलेक्ट्रॉन विन्यास और आवर्त गुणों के अनुसार व्यवस्थित किया गया है। यह वैज्ञानिकों को तत्वों को आसानी से समझने और उनका उपयोग करने में मदद करता है।

Structure of the Periodic Table (आवर्त सारणी की संरचना)

The modern periodic table consists of 118 elements, with each element having its unique atomic number, atomic mass, symbol, and chemical properties. The table is divided into groups (columns) and periods (rows).

Groups and Periods (समूह और आवर्त)

• Groups: There are 18 vertical columns, called groups. Elements in the same group share similar properties.
• Periods: The 7 horizontal rows are called periods. Elements in the same period have the same number of electron shells.

Group	Period
Alkali Metals (Group 1)	1st Period (H, He)
Alkaline Earth Metals (Group 2)	2nd Period (Li to Ne)
Halogens (Group 17)	6th Period (Cs to Rn)

Atomic Number and Mass (परमाणु संख्या और द्रव्यमान)

Each element on the periodic table is characterized by its atomic number (number of protons) and atomic mass (sum of protons and neutrons). The atomic number is located at the top of each element box, while the atomic mass is usually displayed at the bottom.

परमाणु संख्या प्रत्येक तत्व के परमाणु में प्रोटॉन की संख्या को दर्शाती है। परमाणु द्रव्यमान प्रोटॉन और न्यूट्रॉन का कुल योग होता है।

Element	Symbol	Atomic Number	Atomic Mass
Hydrogen	H	1	1.008
Carbon	C	6	12.011
Oxygen	O	8	15.999
Iron	Fe	26	55.845

Types of Elements (तत्वों के प्रकार)

The elements in the periodic table can be categorized into three main groups:

1. Metals (धातु)

Metals are generally good conductors of electricity and heat, malleable, and shiny. Most elements in the periodic table are metals.

• Examples: Iron (Fe), Copper (Cu), Gold (Au)

2. Non-metals (अधातु)

Non-metals are poor conductors of heat and electricity. They are brittle and can exist in solid, liquid, or gaseous states.

• Examples: Oxygen (O), Nitrogen (N), Sulfur (S)

3. Metalloids (उपधातु)

Metalloids have properties that are intermediate between metals and non-metals.

• Examples: Silicon (Si), Boron (B)

Key Elements and Their Uses (प्रमुख तत्व और उनके उपयोग)

1. Hydrogen (H)

• Atomic Number: 1
• Atomic Mass: 1.008
• Uses: Hydrogen is used in fuel cells, rocket fuel, and industrial processes.

2. Oxygen (O)

• Atomic Number: 8
• Atomic Mass: 15.999
• Uses: Essential for respiration in living organisms and combustion.

3. Carbon (C)

• Atomic Number: 6
• Atomic Mass: 12.011
• Uses: Forms the basis of all known life forms, used in fossil fuels and organic chemistry.

4. Iron (Fe)

• Atomic Number: 26
• Atomic Mass: 55.845
• Uses: Widely used in construction, steel production, and manufacturing.

Periodic Table Layout (आवर्त सारणी का लेआउट)

The modern periodic table arranges elements by increasing atomic number and groups them into metals, non-metals, and metalloids.

• Group 1: Alkali Metals (e.g., Lithium, Sodium)
• Group 2: Alkaline Earth Metals (e.g., Magnesium, Calcium)
• Group 17: Halogens (e.g., Fluorine, Chlorine)
• Group 18: Noble Gases (e.g., Helium, Neon)

Special Elements (विशेष तत्व)

• Lanthanides and Actinides: These are placed separately at the bottom of the table.

Element Series	Elements
Lanthanides	Cerium (Ce) to Lutetium (Lu)
Actinides	Thorium (Th) to Lawrencium (Lr)

Elements with Atomic Number and Mass (परमाणु संख्या और द्रव्यमान वाले तत्व)

Here’s the full periodic table with atomic number, symbols, element names, and atomic masses:

Atomic Number	Symbol	Element Name	Atomic Mass
1	H	Hydrogen	1.008
2	He	Helium	4.0026
3	Li	Lithium	6.94
4	Be	Beryllium	9.0122
5	B	Boron	10.81
6	C	Carbon	12.011
7	N	Nitrogen	14.007
8	O	Oxygen	15.999
9	F	Fluorine	18.998
10	Ne	Neon	20.180
11	Na	Sodium	22.990
12	Mg	Magnesium	24.305
13	Al	Aluminium	26.9815
14	Si	Silicon	28.085
15	P	Phosphorus	30.9738
16	S	Sulfur	32.06
17	Cl	Chlorine	35.45
18	Ar	Argon	39.948
19	K	Potassium	39.0983
20	Ca	Calcium	40.078
21	Sc	Scandium	44.9559
22	Ti	Titanium	47.867
23	V	Vanadium	50.9415
24	Cr	Chromium	51.9961
25	Mn	Manganese	54.938
26	Fe	Iron	55.845
27	Co	Cobalt	58.933
28	Ni	Nickel	58.6934
29	Cu	Copper	63.546
30	Zn	Zinc	65.38
31	Ga	Gallium	69.723
32	Ge	Germanium	72.63
33	As	Arsenic	74.9216
34	Se	Selenium	78.96
35	Br	Bromine	79.904
36	Kr	Krypton	83.798
37	Rb	Rubidium	85.4678
38	Sr	Strontium	87.62
39	Y	Yttrium	88.9059
40	Zr	Zirconium	91.224
41	Nb	Niobium	92.9064
42	Mo	Molybdenum	95.95
43	Tc	Technetium	[98]
44	Ru	Ruthenium	101.07
45	Rh	Rhodium	102.9055
46	Pd	Palladium	106.42
47	Ag	Silver	107.8682
48	Cd	Cadmium	112.414
49	In	Indium	114.818
50	Sn	Tin	118.71
51	Sb	Antimony	121.760
52	Te	Tellurium	127.6
53	I	Iodine	126.90447
54	Xe	Xenon	131.293
55	Cs	Cesium	132.9055
56	Ba	Barium	137.327
57–71	La-Lu	Lanthanides	[138.905-174]
72	Hf	Hafnium	178.49
73	Ta	Tantalum	180.9479
74	W	Tungsten	183.84
75	Re	Rhenium	186.207
76	Os	Osmium	190.23
77	Ir	Iridium	192.217
78	Pt	Platinum	195.084
79	Au	Gold	196.966569
80	Hg	Mercury	200.59
81	Tl	Thallium	204.38
82	Pb	Lead	207.2
83	Bi	Bismuth	208.9804
84	Po	Polonium	[209]
85	At	Astatine	[210]
86	Rn	Radon	[222]
87	Fr	Francium	[223]
88	Ra	Radium	[226]
89–103	Ac-Lr	Actinides	[227-262]
104	Rf	Rutherfordium	[267]
105	Db	Dubnium	[270]
106	Sg	Seaborgium	[271]
107	Bh	Bohrium	[270]
108	Hs	Hassium	[277]
109	Mt	Meitnerium	[278]
110	Ds	Darmstadtium	[281]
111	Rg	Roentgenium	[282]
112	Cn	Copernicium	[285]
113	Nh	Nihonium	[286]
114	Fl	Flerovium	[289]
115	Mc	Moscovium	[290]
116	Lv	Livermorium	[293]
117	Ts	Tennessine	[294]
118	Og	Oganesson	[294]

Understanding the Periodic Table

• Atomic Number: Represents the number of protons in an atom.
• Atomic Mass: The total weight of protons and neutrons in an atom’s nucleus.

Important Features of Periodic Table (आवर्त सारणी की महत्वपूर्ण विशेषताएँ)

• Periodic Trends: The periodic table helps to predict chemical reactivity, electronegativity, and ionization energy of elements.
• Valency: Elements in the same group usually have the same valency.
• Atomic Radius: It decreases across a period and increases down a group.

Modern Periodic Law (आधुनिक आवर्त नियम)

According to the modern periodic law, the properties of elements are periodic functions of their atomic numbers. This means that elements with similar atomic numbers tend to have similar properties.

आधुनिक आवर्त नियम के अनुसार, तत्वों के गुणधर्म उनके परमाणु संख्या के आवर्त फलन होते हैं। इसी वजह से समान परमाणु संख्या वाले तत्व समान रासायनिक गुणधर्म दिखाते हैं।

Conclusion (निष्कर्ष)

The periodic table is one of the most important tools in chemistry. It provides essential information about each element’s properties, atomic number, and atomic mass, which are crucial for understanding chemical reactions and bonding.

आवर्त सारणी रसायन विज्ञान का एक महत्वपूर्ण हिस्सा है, जो हमें तत्वों के गुणों और उनके आपसी संबंधों को समझने में मदद करता है। इसका उपयोग वैज्ञानिक अनुसंधान और शैक्षिक उद्देश्यों के लिए किया जाता है।

External Resources (बाहरी संसाधन)

• Interactive Periodic Table
• IUPAC Periodic Table