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प्रश्न
The atomic number of four elements A, B, C and D are 12, 13, 15 and 3 respectively. The element which cannot form a cation is :
पर्याय
A
B
C
D
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उत्तर
C
Element C has 15 electrons; so, the electronic configuration is 2 , 8 , 5. This element will gain 3 electrons in order to complete its octet; so, it cannot form cations.
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संबंधित प्रश्न
What are the atomic numbers of elements whose outermost electrons is represented by 2p3.
What are the atomic numbers of elements whose outermost electrons is represented by 3p5?
Tick the most appropriate answer.
Which of these have similar chemical properties but different set of physical properties and mass number?
- isobars
- elements
- isotopes
- none of these
From the symbol `""_15^31"P"`, state :
(i) mass number of phosphorus,
(ii) atomic number of phosphorus, and
(iii) electron configuration of phosphorus.
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
Draw the atomic diagram of the following element showing the distribution of – protons, neutrons and the electrons in the various shell of the atom.
Carbon – \[\ce{^12_6C}\]
[The upper number represent the – mass number and the lower number represent the – atomic number e.g. calcium – mass number = 40, atomic number = 20]
The diagram represents an isotope of hydrogen [H]. Answer the following:
Atomic no. = 1
Mass no. = 1
If an isotope of ‘H’ has mass no. = 2, how many electrons does it have.
Draw the structure of the following atoms showing the nucleus containing – protons, neutrons and the orbits with the respective electron:
Lithium [At. no. = 3, Mass no. = 7]
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’.
What is atomic number?
