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प्रश्न
State how electrons are distributed in an atom. Explain in brief the rules which govern their distribution.
उत्तर
(a) Electrons revolve around the nucleus in imaginary paths called shells or orbits. Shells start from the nucleus to outwards.
Rules: The maximum number of electrons in a shell is given by 2n2. Where n is the number of shell i.e. 1st shell can have a maximum of 2 electrons.
2n2 = 2(1)2 = 2 × 1 = 2
2nd shell can have maximum of 8 electrons
2n2 = 2(2)2 = 2 × 4 = 8
3rd shell can have maximum of 18 electrons
2n2 = 2 (3)2 = 2 × 9 = 18 and so on….
(b) Outer most orbit cannot have more than 8 electrons and 18 in penultimate orbit.
(c) A new shell cannot start until previous is filled completely.
APPEARS IN
संबंधित प्रश्न
Fill in the blank
Neutrons are .......................... particles having mass equal to that of protons.
Write true or false for the following statement
The central pad of the atom is called nucleus.
Define the term Atomic number.
What are the two main parts of which an atom is made of?
Tick the most appropriate answer.
In 1908, R A Millikan found the charge of an electron to be
- 1.6 x 10-19 C
- 1.6 x 10-15 C
- 1.4 x 10-19 C
- 1.6 x 19-16 C.
TRUE \ FALSE
Electrons are present in the nucleus.
WRITE SHORT ANSWER
Name the isotopes of hydrogen.
WRITE SHORT ANSWER
What is the charge on a neutron ?
Compare an electron, a proton and a neutron in respect of their relative masses and charges.
Name the sub-atomic particle whose charge is 0.
