First 20 Elements - Meaning, Definition, Examples, Periodic Table, FAQs

Elements are arranged systematically in the periodic table. The arrangement of elements is on the basis of their chemical properties such as atomic number, electronic configuration and recurring chemical properties. Inside the periodic table, the arrangement of elements is in the form of rows and columns. The rows are called periods and the columns are called groups. The first 20 elements of the periodic table are the fundamental building blocks of matter and predict the periodic trends that influence their behaviour.

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First 20 elements:

Any substance that cannot be broken down chemically into simple molecules is called an element. An element is made up of atoms with the same atomic number, which means that each atom will have the same amount of protons in the nucleus like the other atoms in the component.

First 20 elements Of The Periodic Table

The periodic table is the representation of elements in the increasing order of their atomic number.

The first twenty elements in the periodic table ranging from atomic numbers 1-20 is

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The atomic number of the first twenty elements is given in 1^st column while the symbol of the first 20 elements' name is given in the last column.

An in-depth of the first 20 elements in the periodic table is useful. Six of these elements make up nearly all of the mass of the human body. The first 20 elements provide an excellent overview of the various element groups. They can also be found in more common chemical processes. The elements are given in ascending atomic numbers 1 to 20 order. The atomic number refers to the number of protons in each element's atoms.

Name and Symbols of Elements:

The atomic number, element name, or element symbol can all be used to identify elements. A one- or two-letter abbreviation of the name serves as the emblem. Some symbols, on the other hand, allude to old element names. The symbol for sodium, for given as Na. This is a reference to the Latin word natrium, which was once used to refer to caustic soda. In Latin, the name of the atomic no of sodium is found to be atrium. Potassium's symbol is K, which is derived from the Latin word kalium, which denoted alkali or potash. An element symbol's initial letter is capitalised. It's lowercase when there's a second letter.

Examination of 1 to 20 elements of the periodic table:

1. Hydrogen

Under normal circumstances, hydrogen is a nonmetallic, colourless gas. It transforms into an alkali metal under great pressure. This element has three isotopes, each with a different amount of neutrons in its atoms. Protium is the most prevalent isotope. Deuterium and tritium are the other two.

1. The atomic number of Hydrogen is 1

2. H is its symbol

3. It is estimated to have an atomic mass value of 1.008 amu

4. H is assigned 1s¹ configuration

5. It is a Nonmetal belonging to group 1 and s-block

2. Helium

1. Helium is a light gas with no visible colour.

2. The atomic number of Helium is 2

3. He is its symbol

4. It is estimated to have an atomic mass value of 4.002 amu

5. He is assigned 1s² configuration

6. It is belonging to group 18 and s-block

3. Lithium

It is a highly reactive solid metal with a silver colour

1. The atomic number of Lithium is 3

2. Li is its symbol

3. It is estimated to have an atomic mass value of 6.94 amu

4. Li is assigned [He] 2s¹ configuration

5. It is an alkali metal belonging to group 1 and s-block.

4. Beryllium

It is a solid material with a shiny grey- white appearance

1. The atomic number of beryllium is 4

2. Be is its symbol

3. It is estimated to have an atomic mass value of 9.012 amu

4. Be is assigned [He] 2s² configuration

5. It is an alkaline earth metal belonging to group 2 and s-block.

5. Boron

1. The atomic number of Boron is 5

2. B is its symbol

3. It is estimated to have an atomic mass value of 10.81 amu

4. B is assigned [He] 2s² 2p¹ configuration

5. It is a metalloid belonging to group 13 and p-block.

6. Carbon

1. The atomic number of carbon is 6

2. C is its symbol

3. It is estimated to have an atomic mass value of 12.011 amu

4. C is assigned [He] 2s² 2p² configuration

5. It is a metalloid belonging to group 14 and p-block

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7. Nitrogen

1. the atomic number of nitrogen is 7

2. N is its symbol

3. It is estimated to have an atomic mass value of 14.007 amu

4. N is assigned [He] 2s² 2p³ configuration

5. It belongs to group 15 and p-block.

8. Oxygen:

1. The atomic number of oxygen is 8

2. O is its symbol

3. It is estimated to have an atomic mass value of 16 amu

4. O is assigned [He] 2s² 2p⁴ configuration

5. It is belonging to group 16 and p-block

9. Fluorine:

1. The atomic number of fluorine is 9

2. F is its symbol

3. It is estimated to have an atomic mass value of 18.989 amu

4. F is assigned [He] 2s² 2p⁵ configuration

5. It is belonging to group 17 and p-block

10. Neon:

1. the atomic number of neon is 10

2. Ne is its symbol

3. It is estimated to have an atomic mass value of 20.179 amu

4. N is assigned [He] 2s² 2p⁶ configuration

5. It is belonging to group 18 and p-block

11. Sodium:

1. The atomic number of sodium is 11

2. Na is the symbol of sodium

3. The Latin name of sodium is Natrium

4. It is estimated to have an atomic mass value of 22.989 amu

5. F is assigned [Ne] 3s¹ configuration

6. It is belonging to group 1 and s-block

12. Magnesium:

1. The atomic number of magnesium is 12

2. Mg is its symbol

3. It is estimated to have an atomic mass value of 24.309 amu

4. Mg is assigned [Ne] 3s² configuration

5. It is belonging to group 2 and s-block

13. Aluminium:

1. The atomic number of aluminium is 13

2. Al is its symbol

3. It is estimated to have an atomic mass value of 26.968 amu

4. Al is assigned [Ne] 3s² 3p¹ configuration

5. It is belonging to group 13 and p-block

14. Silicon

1. The atomic number of Silicon is 14

2. Si is its symbol

3. It is estimated to have an atomic mass value of 28.085 amu

4. Si is assigned [Ne] 3s² 3p² configuration

5. It belongs to group 14 and p-block.

15. Phosphorous:

1. The atomic number of Phosphorous is 15

2. Pis its symbol

3. It is estimated to have an atomic mass value of 30.9737 amu

4. P is assigned [Ne] 3s² 3p³ configuration

5. It is belonging to group 15 and p-block

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1. Sulphur:

2. The atomic number of Sulfer is 16

3. S is its symbol

4. It is estimated to have an atomic mass value of 32.09 amu

5. S is assigned [Ne] 3s² 3p⁴ configuration

6. It is belonging to group 16 and p-block

17. Chlorine

1. The atomic number of Chlorine is 17.

2. Cl is its symbol

3. It is estimated to have an atomic mass value of 35.45 amu

4. Cl is assigned [Ne] 3s² 3p⁵ configuration

5. It is belonging to group 17 and p-block

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18. Argon

1. the atomic number of argon is 18

2. Ar is its symbol

3. It is estimated to have an atomic mass value of 39.948 amu

4. Ar is assigned [Ne] 3s² 3p⁶ configuration

5. It is belonging to group 18 and p-block

19. Potassium:

1. The atomic number of Potassium is 19

2. The Latin name of potassium is found to be Kalium

3. K is its symbol

4. It is estimated to have an atomic mass value of 39.093 amu

5. K is assigned [Ar] 4s¹ configuration

6. It is belonging to group 1 and s-block

20. Calcium:

• The atomic number of Calcium is 20.

• Ca is its symbol

• It is estimated to have an atomic mass value of 40.10 amu

• Ca is assigned [Ar] 4s¹ configuration

• It is belonging to group 14 and s-block

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Some Solved Examples

Example.1 Choose the correct option:

1) (correct)The period of the element is determined by its highest shell

2)The period of the element is determined by its last orbital

3)The period of the element is determined its valence shell electrons

4)The period of the element is determined by its valency

Solution

The period of the element is determined by its highest shell.

Hence, the answer is the option (1).

Example.2 Which pair of atomic numbers represents s-block elements

1)7,15

2)6,12

3)9,17

4) (correct)3,12

Solution

Out of the given elements, Z= 3 (Li) and Z= 12 (Mg) belong to the s Block of the periodic table.

Hence, the answer is the option (4).

Example.3 Newland’s octave law was successful in arranging:

1)Heavier elements

2) (correct)Lighter elements

3)Both

4)None

Solution

Newland’s octave law was successful in arranging lighter elements. After calcium, this law did not work accordingly.

Hence, the answer is the option (2).

Summary

The first 20 elements of the periodic table possess a range of chemical properties and their uses from simplest to most abundant elements like hydrogen and some essential elements of earth such as carbon, nitrogen and hydrogen these three elements are the main building blocks of many processes and also plays a vital role in the chemistry field and has various technological applications. Their characteristics are very diverse and interconnected. The first 20 elements of the periodic table contain metals such as sodium, magnesium, and aluminium. Metalliods such as silicon, and boron. Also, contains noble gases like neon and argon. Understanding all these elements helps us to appreciate the balance of nature and their application in chemistry.