मराठी

An Element a Atomic Number 7 Mass Numbers 14 B Electronic Configuration 2,8,8 C Electrons 13, Neutrons 14

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प्रश्न

An element A atomic number 7 mass numbers 14
B electronic configuration 2,8,8
C electrons 13, neutrons 14
D Protons 18 neutrons 22
E Electronic configuration 2,8,8,1

State Valency of each element

An element A atomic number 7 mass numbers 14

B electronic configuration 2,8,8

C electrons 13, neutrons 14

D Protons 18 neutrons 22

E Electronic configuration 2,8,8,1

State (i) Valency of each element (ii) which one is a metal (iii) which is non-metal (iv) which is an inert gas

टीपा लिहा
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उत्तर

(i) Element A
Atomic number = 7 = Number of electrons = 2, 5
Valency of A = 8 - 5 = 3

Element B
Electronic configuration 2, 8, 8
Valency of B = Zero

Element C has 13 electrons
Electronic configuration = 2, 8, 3
Valency of C = 3

Element D
Protons = 18 = Electrons = 2, 8, 8
Valency of D = Zero

Element E
Electronic configuration = 2, 8, 8, 1
Valency of E = 1

(ii) C and E are metals.

(iii) A is a non-metal.

(iv) A, C and E are not inert gases.

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पाठ 4: Atomic Structure and Chemical Bonding - Exercise 4 (C) [पृष्ठ ६७]

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सेलिना Concise Chemistry [English] Class 9 ICSE
पाठ 4 Atomic Structure and Chemical Bonding
Exercise 4 (C) | Q 21 | पृष्ठ ६७

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