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प्रश्न
Name the elements in the correct order of their increasing atomic numbers present in the first, second, and third short periods of the periodic table.
State which of the elements are –
- metallic
- non-metallic
- noble gases
in each of the periods 2 and 3.
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उत्तर
Names of elements of:
| Period first | Hydrogen | Helium |
| H | He |
| Period – 2 | Li | Be | B | C | N | O | F | Ne |
| Lithium | Beryllium | Boron | Carbon | Nitrogen | Oxygen | Fluorine | Neon |
| Period – 3 | Na | Mg | Al | Si | P | S | Cl | Ar |
| Sodium | Magnesium | Alummium | Silicon | Phosphorus | Sulphur | Chlorine | Argo |
- Metals: Li, Be, Na, Mg, Al
- Non-metals: C, N, O, F, P, S, Cl
- Noble – gases: Ne, Ar
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संबंधित प्रश्न
Write the number of vertical columns in the modern periodic table. What are these columns called?
Which element has the electronic configuration 2, 8, 2?
Match the atomic number 2, 4, 8, 15 and 19 with each of the following:
- A solid non-metal belonging to the third period.
- A metal of valency 1.
- A gaseous element with valency 2.
- An element belonging to Group 2.
- A rare gas.
An element with the atomic number 19 will most likely combine chemically with the element whose atomic number is ______.
How does the number of valence electrons vary on moving from left or right in the second period of the periodic table?
Why are noble gases placed in a separate group?
Arrange the following according to the instruction given in the bracket:
K, Pb, Ca, Zn (in the increasing order of the reactivity).
Arrange the following as per instruction given in the bracket.
Cl, F, Br, I (increasing electron affinity)
Name and state the following with reference to the elements of the first three periods of the periodic table.
Non-metallic elements present in Period 3 of Groups 15 and 16.
Going across a period left to right, atomic size _____.
