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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The atomic number of the first twenty elements is given in 1st column while the symbol of the first 20 elements' name is given in the last column.
Atomic numbers 1 to 20 | Element | Symbol |
Hydrogen | H | |
Helium | He | |
Lithium | Li | |
Berilliyum | Be | |
Boron | B | |
Carbon | C | |
Nitrogen | N | |
Oxygen | O | |
Fluorine | F | |
Neon | Ne | |
Sodium | Na | |
Magnesium | Mg | |
Aluminium | Al | |
Silicon | Si | |
Phosphorous | P | |
Sulfur | S | |
Chlorine | Cl | |
Argon | Ar | |
Potassium | K | |
calcium | Ca |
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.
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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.
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, 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.
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.
The atomic number of Hydrogen is 1
H is its symbol
It is estimated to have an atomic mass value of 1.008 amu
H is assigned 1s1 configuration
It is a Nonmetal belonging to group 1 and s-block
Helium is a light gas with no visible colour.
The atomic number of Helium is 2
He is its symbol
It is estimated to have an atomic mass value of 4.002 amu
He is assigned 1s2 configuration
It is belonging to group 18 and s-block
It is a highly reactive solid metal with a silver colour
The atomic number of Lithium is 3
Li is its symbol
It is estimated to have an atomic mass value of 6.94 amu
Li is assigned [He] 2s1 configuration
It is an alkali metal belonging to group 1 and s-block.
It is a solid material with a shiny grey- white appearance
The atomic number of beryllium is 4
Be is its symbol
It is estimated to have an atomic mass value of 9.012 amu
Be is assigned [He] 2s2 configuration
It is an alkaline earth metal belonging to group 2 and s-block.
The atomic number of Boron is 5
B is its symbol
It is estimated to have an atomic mass value of 10.81 amu
B is assigned [He] 2s2 2p1 configuration
It is a metalloid belonging to group 13 and p-block.
The atomic number of carbon is 6
C is its symbol
It is estimated to have an atomic mass value of 12.011 amu
C is assigned [He] 2s2 2p2 configuration
It is a metalloid belonging to group 14 and p-block
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the atomic number of nitrogen is 7
N is its symbol
It is estimated to have an atomic mass value of 14.007 amu
N is assigned [He] 2s2 2p3 configuration
It belongs to group 15 and p-block.
The atomic number of oxygen is 8
O is its symbol
It is estimated to have an atomic mass value of 16 amu
O is assigned [He] 2s2 2p4 configuration
It is belonging to group 16 and p-block
The atomic number of fluorine is 9
F is its symbol
It is estimated to have an atomic mass value of 18.989 amu
F is assigned [He] 2s2 2p5 configuration
It is belonging to group 17 and p-block
the atomic number of neon is 10
Ne is its symbol
It is estimated to have an atomic mass value of 20.179 amu
N is assigned [He] 2s2 2p6 configuration
It is belonging to group 18 and p-block
The atomic number of sodium is 11
Na is the symbol of sodium
The Latin name of sodium is Natrium
It is estimated to have an atomic mass value of 22.989 amu
F is assigned [Ne] 3s1 configuration
It is belonging to group 1 and s-block
The atomic number of magnesium is 12
Mg is its symbol
It is estimated to have an atomic mass value of 24.309 amu
Mg is assigned [Ne] 3s2 configuration
It is belonging to group 2 and s-block
The atomic number of aluminium is 13
Al is its symbol
It is estimated to have an atomic mass value of 26.968 amu
Al is assigned [Ne] 3s2 3p1 configuration
It is belonging to group 13 and p-block
The atomic number of Silicon is 14
Si is its symbol
It is estimated to have an atomic mass value of 28.085 amu
Si is assigned [Ne] 3s2 3p2 configuration
It belongs to group 14 and p-block.
The atomic number of Phosphorous is 15
Pis its symbol
It is estimated to have an atomic mass value of 30.9737 amu
P is assigned [Ne] 3s2 3p3 configuration
It is belonging to group 15 and p-block
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The atomic number of Sulfer is 16
S is its symbol
It is estimated to have an atomic mass value of 32.09 amu
S is assigned [Ne] 3s2 3p4 configuration
It is belonging to group 16 and p-block
The atomic number of Chlorine is 17.
Cl is its symbol
It is estimated to have an atomic mass value of 35.45 amu
Cl is assigned [Ne] 3s2 3p5 configuration
It is belonging to group 17 and p-block
NCERT Chemistry Notes:
the atomic number of argon is 18
Ar is its symbol
It is estimated to have an atomic mass value of 39.948 amu
Ar is assigned [Ne] 3s2 3p6 configuration
It is belonging to group 18 and p-block
The atomic number of Potassium is 19
The Latin name of potassium is found to be Kalium
K is its symbol
It is estimated to have an atomic mass value of 39.093 amu
K is assigned [Ar] 4s1 configuration
It is belonging to group 1 and s-block
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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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).
The first element of the periodic table is hydrogen and the 20th element of the periodic element is Calcium.
Atomic number of Sodium 11 is and that of potassium is 19.
In Latin the name of sodium is found to be natrium .
Kalium is found to be the latin name of potassium.
Aluminium has the chemical symbol Al.
The first 20 elements in order are Hydrogen, Helium, Lithium, Beryllium, Boron, Carbon, Nitrogen, Oxygen, Fluorine, Neon, Sodium, Magnesium, Aluminium, Silicon, Phosphorus, Sulphur, Chlorine, Argon, Potassium, and Calcium.
Hydrogen and helium are the oldest and the most abundant elements on the earth.
The periodic table contains total 118 elements
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