Q1
What are the first 20 elements in order?
- H – Hydrogen
- He – Helium
- Li – Lithium
- Be – Beryllium
- B – Boron
- C – Carbon
- N – Nitrogen
- O – Oxygen
- F – Fluorine
- Ne – Neon
- Na – Sodium
- Mg – Magnesium
- Al – Aluminium
- Si – Silicon
- P – Phosphorus
- S – Sulphur
- Cl – Chlorine
- Ar – Argon
- K – Potassium
- Ca – Calcium
Q2
Define Element Symbols and Numbers.
The number of the element is its atomic number, that is the number of protons in the nucleus for every atom of that element. While the element symbol is a one- or two-letter abbreviation of the element’s name. It can also refer to an old name. (K, for example, stands for kalium).
Q3
What is the Atomic Mass of Elements?
The total mass of one atom of a specific element is defined as the atomic mass of that element. Its unit is termed the unified atomic mass unit and is signified by the symbol ‘u’.
Standard atomic weight is utilised to deliver the value of the mean of the atomic masses in a mixture of isotopes in a provided sample of an element.
Q4
Why are the first 20 elements so important?
About 99% of the mass of the human body is made of six of these elements. The first 20 elements provide a great overview of the various element groups. They can also be found in more common chemical processes.
Q5
How are the first 20 elements arranged in the periodic table?
The periodic table lists the elements in order of increasing atomic number. This has been also the number of protons in each atom. The first 20 items are listed in the following order: H stands for hydrogen.
Q6
What are the metal(s) and non-metals in the first 20 elements?
Lithium, Beryllium, Sodium, Magnesium, Aluminium, Potassium, and Calcium are metals in the first twenty elements. Hydrogen, Helium, Carbon, Nitrogen, Oxygen, Fluorine, Neon, Phosphorous, Sulphur, Chlorine, and Argon are the non-metals in the first twenty elements.
Q7
What are the electrons of the first 5 elements?
1) Hydrogen (H): Valency : 1 , Valence electrons : 1
2) Helium (He): Valency : 0, Valence electrons : 2
3) Lithium (Li): Valency : 1, Valence electrons : 1
4) Beryllium (Be): Valency : 2, Valence electrons : 2
5) Boron (B): Valency : 3, Valence electrons : 3
Q8
Which of the first 20 elements do not form compounds easily and why?
Noble gases except He, have complete s and p outer electron shells. So they are not easily involved in chemical reactions and bond formations.
Q9
Which of the first 20 elements are noble gases?
There are three noble gases in the first 20 elements: Helium (He), Neon (Ne), and Argon (Ar). Helium has an atomic number 2, Neon has an atomic number of 10, while Argon has an atomic number of 18.
Q10
How many periods are in the periodic table?
The periodic table of the elements lists all of the chemical elements that have been discovered or created; they are organised into seven horizontal periods in the order of their atomic numbers, with the lanthanoids, lanthanum, 57, to lutetium, 71, and actinoids, actinium, 89, to lawrencium, 103 mentioned independently.
