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प्रश्न
State the number of elements in periods 1, Periods 2, and Period 3 of the periodic table. Name them.
उत्तर
Period 1 has two elements: Hydrogen (H) and Helium (He).
Period 2 has 8 elements: Lithium (Li), Beryllium (Be), Boron (B), Carbon (C), Nitrogen (N), Oxygen (O), Fluorine (F), and Neon (Ne).
Period 3 has 8 elements: Sodium (Na), Magnesium (Mg), Aluminium (Al), Silicon (Si), Phosphorus (P), Sulphur (S), Chlorine (Cl), and Argon (Ar).
संबंधित प्रश्न
Na, Mg and Al are the elements of the same period of Modern Periodic Table having, one, two and three valence electrons respectively. Which of these elements (i) has the largest atomic radius, (ii) is least reactive? Justify your answer stating reason for each case.
Define the term : Valency
Which element has the electronic configuration 2, 8, 2?
An element with the atomic number 19 will most likely combine chemically with the element whose atomic number is ______.
What happens to the metallic character of the elements as we go down in a group of the periodic table?
What is meant by a group in the periodic table?
Element P has atomic number 19. To which group and period, does P belong? Is it a metal or a non-metal? Why?
Moving down in the second group, number of valence electrons ______.
The electronic configuration of an element is 2, 8, 4. State it:
group and period in the Modern Periodic Table.
Write the electronic configuration of two elements A and B whose atomic numbers are 20 and 17 respectively. Write the molecular formula of the compound formed when element A reacts with element B. State whether this compound is acidic, basic or neutral. Give a reason to justify your answer.
