Advertisements
Advertisements
प्रश्न
Two elements X and Y have valencies of 5 and 3, and 3 and 2, respectively. The elements X and Y are most likely to be respectively :
विकल्प
copper and sulphur
sulphur and iron
phosphorus and nitrogen
nitrogen and iron
Advertisements
उत्तर
nitrogen and iron
Elements X and Y, most likely, are nitrogen and iron.
APPEARS IN
संबंधित प्रश्न
Explain the terms 'valency' and 'variable valency'.
An atom of an element is denoted by a “symbol”. Explain the meaning of the term ‘symbol’. State a reason for representing the following element by its symbol.
Hydrogen by ‘H’
Match the metallic elements – with their correct symbols Metallic elements
| Metallic elements | Symbol |
| (a) Potassium | (1) Ca |
| (b) Sodium | (2) Zn |
| (c) Calcium | (3) Pb |
| (d) Magnesium | (4) Hg |
| (e) Zinc | (5) Cu |
| (f) Aluminum | (6) Au |
| (g) Iron | (7) K |
| (h) Lead | (8) Fe |
| (i) Copper | (9) Al |
| (j) Mercury | (10) Na |
| (k) Silver | (11) Mg |
| (l) Platinum | (12) Pt |
| (m) Gold | (13) Ag |
Match the noble gases – with their correct symbols:
| Noble gases | Symbols |
| (a) Helium | (1) Ar |
| (b) Neon | (2) Xe |
| (c) Argon | (3) Rn |
| (d) Krypton | (4) He |
| (e) Xenon | (5) Kr |
| (f) Radon | (6) Ne |
Match the symbols of – radicals – with their correct combining power or capacity, (valency).
(a) OH
(b) So4
(c) No3
(d) Co3
Combining power or capacity – A : 3; B : 2; C : 1. (negative valencies)
Give the symbol of the following element:
Boron
Write the radical of the following valency:
Aluminium
Write the radical of the following valency:
Sulphur [Sulphide]
State the valency of the following metallic element and write symbol with the valency
Sodium
The first letter of a symbol is always written as a ______ letter and the second letter as a ______ letter.
