Advertisements
Advertisements
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
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.
APPEARS IN
संबंधित प्रश्न
Dalton said that ______ could not be divided.
Give the following a suitable word/phrase.
Atoms of same element with same atomic number but a different mass number.
Fill in the following blanks :
| Atomic Number | Mass Number | Protons | Neutrons | Electrons | Symbol |
| 10 | 22 | _________ | _________ | _________ | _________ |
State why the atomic weight of an element is also termed relative atomic mass.
If an atom ‘A’ has atomic number 19 and mass number 39, state –
- Its electronic configuration.
- The number of valence electrons it possesses.
Draw the atomic diagram of the following element showing the distribution of – protons, neutrons and the electrons in the various shell of the atom.
Oxygen – \[\ce{^16_8O}\]
[The upper number represent the – mass number and the lower number represent the – atomic number e.g. calcium – mass number = 40, atomic number = 20]
An element ‘A’ has mass number 23 and atomic number 11. State the –
- no. of neutrons in its shell,
- electronic configuration of the element ‘A’.
The ratio of the radii of hydrogen atom and its nucleus is ~ 105. Assuming the atom and the nucleus to be spherical,
- what will be the ratio of their sizes?
- If atom is represented by planet earth ‘Re ’ = 6.4 ×106 m, estimate the size of the nucleus.
Explain the following terms.
- Proton
- Electron
- Neutron.
Mass No. 27 is for the element ______.
