Advertisements
Advertisements
प्रश्न
An element A has 2 electrons in its fourth shell. State:
its atomic number
उत्तर
Its atomic number is 20.
APPEARS IN
संबंधित प्रश्न
The atomic number of an element is more important to the chemist than its relative atomic mass. Why?
Complete the table:
|
Atomic number |
Element |
Electronic configuration |
Select an element of the same group |
|
11 |
Sodium |
|
(Ca/N/K)… |
|
15 |
Phosphorus |
|
(Ba/N/Rb)… |
|
16 |
Sulphur |
|
(F/Cl/O)… |
|
9 |
Fluorine |
|
(Ca/Cl/K)… |
Relative atomic mass of a light element up to calcium is approximately ______ its atomic number.
What is meant by ‘period number’. What does it signify?
Give a reason for the following:
Properties of elements are periodic functions of their atomic numbers and not atomic weights.
In Modern Periodic Table the number of columns and periods are respectively _______ and _______.
Modern periodic law states that the physical and chemical properties of elements are the periodic functions of their ______.
State modern periodic law.
The basis of modern periodic law is ______.
| Group in the modern periodic table | Families |
| 1 | ______ |
| ______ | Transition metals |
| ______ | Boron family |
| 15 | ______ |
| 17 | ______ |
