Advertisements
Advertisements
प्रश्न
What is the contribution of the following in atomic structure?
Democritus
Advertisements
उत्तर
Democritus called paramanu as atom which comes from the Greek word atomos, meaning indivisible.
APPEARS IN
संबंधित प्रश्न
Among the following compounds identify the compound that has all three bonds (ionic, covalent and coordinate bond).
State the following is a reduction reaction or oxidation reaction.
\[\ce{A^3+ + e- -> A^2+}\]
Name an element which does not contain neutron.
Define the term:
orbit
Name the following:
An element having valency 'zero'
\[\ce{^24_12Mg}\] and \[\ce{^26_12Mg}\] are symbols of isotopes of magnesium.
(a) Compare the atoms of these isotopes with respect to :
i. the composition of their nuclei
ii. their electronic configurations
(b) Give reasons why the two isotopes of magnesium have different mass numbers.
Copy and complete the following table relating to the atomic structure of some elements:
| Element | Atomic Number | Mass Number | Number of protons | Number of Neutrons | Number of Electrons |
| Beryllium | 4 | 9 | |||
| Fluorine | 9 | 10 | |||
| Sodium | 12 | 11 | |||
| Aluminium | 27 | 13 | |||
| Phosphorus | 31 | 15 |
Choose the odd one out and write the reason:
Complete the following table:
| a. | Dativebond | ______ |
| b. | CaH2 → Ca+H2 | ______ |
| c. | ______ | Reduction |
| d. | ______ | Redox reaction |
How many electrons are required or released by each atom in chlorine to attain the nearest noble gas configuration?
