Question

Define Valency urgently

Answer 1

What is valency ?

=> Valency is the combining capacity of an atom with another atom (s) .

This is normally given by the number of Valence electrons or by 8 minus the Valence electrons (Only when the number of Valence electrons is more than 4) .

Valency of first 20 elements is given below.
1) Hydrogen (H) = 1

2) Helium (He) = 0

3) Lithium (Li) = 1

4) Beryllium (Be) = 2

5) Boron (B) = 3

6) Carbon (C) = 4

7) Nitrogen (N) = 3

8) Oxygen (O) = 2

9) Fluorine (F) = 1

10) Neon (Ne) = 0

11) Sodium (Na) = 1

12) Magnesium (Mg) = 2

13) Aluminium (Al) = 3

14) Silicon (Si) = 4

15) Phosphorus (P) = 3, 5

16) Sulphur (S) = 2

17) Chlorine (Cl) = 1

18) Argon (Ar) = 0

19) Potassium (K) = 1

20 ) Calcium (Ca) = 2

#Be Brainly !!

Answer 2

$\huge\textbf{Valency :}$


Valency tells us how many electrons does an atom need to loose, gain and share to attain a stability to form a compound.

$\textbf{Valency of First 20 elements are :}$

1) Hydrogen (H) :- +1

2) Helium (He) :- 0

3) Lithium (Li) :- +1

4) Beryllium (Be) :- +2

5) Boron (B) :- +3

6) Carbon (C) :- ±4

7) Nitrogen (N) :- -3

8) Oxygen (O) :- -2

9) Fluorine (F) :- -1

10) Neon (Ne) :- 0

11) Sodium (Na) :- +1

12) Magnesium (Mg) :- +2

13) Aluminium (Al) :- +3

14) Silicon (Si) :- ±4

15) Phosphorus (P) :- -3,-5

16) Sulphur (S) :- -2

17) Chlorine (Cl) :- -1

18) Argon (Ar) :- 0

19) Potassium (K) :- +1

20) Calcium (Ca) :- +2

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