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प्रश्न
What are the atomic numbers of elements whose outermost electrons is represented by 2p3.
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उत्तर
2p3
Completing the electron configuration of the element as
1s2 2s2 2p3.
∴ Number of electrons present in the atom of the element = 2 + 2 + 3 = 7
∴ Atomic number of the element = 7
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संबंधित प्रश्न
Multiple Choice Questions
The sum of number of protons and number of neutrons present in the nucleus of an atom is called its
The atom of an element is made up of 4 protons, 5 neutrons and 4 electrons. What is its atomic number and mass number?
Name the particles which actually determine the mass of an atom.
Fill in the Blank of the Following Statement :
An atom has atomic mass number 23 and atomic number 11. The atom has .................... electrons.
Fill in the blank of the following statement :
All the mass of an atom is concentrated in a small region of space called the ___________.
The properties of the elements are a periodic function of their __________.
The atom of an element is made up of 4 protons, 5 neutrons and 4 electrons. What are its atomic number and mass number?
Elements X, Y and Z have atomic numbers 6,9 and 12 respectively. Which one:
- Forms an anion
- Forms a cation
What are orbits or shells of an atom?
Draw the atomic diagram of the following element showing the distribution of – protons, neutrons and the electrons in the various shell of the atom.
Calcium – \[\ce{^40_20Ca}\]
[The upper number represent the – mass number and the lower number represent the – atomic number e.g. calcium – mass number = 40, atomic number = 20]
Match the statements in List I with the correct answer from List II.
| List I | List II |
| 1. Mass number of an atom is the number of protons and | A: Electron |
| 2. The sub-atomic particle with a negligible mass. | B: Argon |
| 3. An atom having stable electronic configuration. | C: Nitrogen |
| 4. A molecule formed by sharing of electrons [covalency] | D: Sodium |
| 5. A metallic atom having unstable electronic configuration. | E: Neutrons |
Elements A, B and C have atomic numbers 9, 20 and 10 respectively.
- State which one is
(1) a non-metal,
(2) a metal,
(3) chemically inert.[A,B,C] - Write down the formula of the compound formed by two of the above elements.[BA2]
Every atom has an equal number of protons and electrons. The nature of the atom is ______.
The No. of electrons in the outermost shell of the atom of an inert gas ______.
The Atomic number of an element is 20. It has ______ valence electrons.
‘A’ is denoted by ______.
‘Z’ is denoted by ______.
What are the letters A, Z, and X stand for?
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- State its position in the periodic table.
- Is it a metal or a non-metal?
- State the name assigned to this group.
- What is the valency of this element?
A group of elements in the periodic table is given below (Boron is the first member of the group and Thallium is the last).
Boron, Aluminium, Gallium, Indium, Thallium
Answer the following question in relation to the above group of elements:
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