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प्रश्न
Write the number of protons, neutrons and electronic configuration of \[\ce{_19^39K, _15^31P}\]. Also state their position in periodic table.
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उत्तर
Atomic number = Number of protons
Hence, the number of protons in K atom = 19
Number of neutrons = Mass number − Atomic number
Hence, the number of neutrons in K atom = 39 − 19 = 20
Number of electrons = Number of protons
Hence, the number of electrons = 19
And electronic configuration of K atom = 2, 8, 8, 1
Since K atom has 4 shells, hence it belongs to fourth period.
With one valence electron, it belongs to group 1
Number of protons in P atom = 15
Number of neutrons in P atom = 31 − 15 = 16
Number of electrons in P atom = 15
And electronic configuration of P atom = 2, 8, 5
Since it has three shells, it belongs to period 3 and has 5 valence electrons. Phosphorus is found in five plus ten, which is the 15th group.
संबंधित प्रश्न
Which of the following statement is correct in regard to the classification of elements?
(a) Elements in modern periodic table are arranged on the basis of increasing atomic masses.
(b) Elements in Mendeleev's periodic table are arranged on the basis of increasing atomic numbers.
(c) In modern periodic table, the element nickel of lower atomic mass is kept before the element cobalt of higher atomic mass.
(d) In modern periodic table, the isotopes of chlorine having different atomic masses are kept in the same group.
What is the usual number of valence electrons in the atoms of the last element in a period?
State whether the following statement is true or false:
On going down in a group of the periodic table, the number of valence electrons increases.
What is the usual number of valence electrons and valency of group 18 elements of the periodic table?
What is the main characteristic of the last elements in the periods of the periodic table? What is the general name of such elements?
What are horizontal rows and vertical columns in a periodic table known as?
How many periods and groups are there in the modern periodic table?
The d-block elements are called as _______ elements.
Explain giving reason why although the nuclear charge in atoms increases in moving from left to right in a period as well as in moving from top to bottom in a group in the Modern periodic table, but the size of the atoms does not vary similarly in both situations.
Give reason for the following:
Inert gases do not form ion.
