Question

An electronic configuration of some elements are given below
A- [Ne] 3s1
B- [Ar] 4s2
C- [Ar] 3d6 4s2
D- [Ne] 3s2 3p4
a) what is the atomic number of element B
b) from the atomic number of an element B
c) which one of the elements produce two coloured compounds ​

Answer 1

Answer:

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Question 23

:(i) Write the electronic configurations of the following ions: (a) H– (b) Na+ (c) O2–(d) F–

(ii) What are the atomic numbers of elements whose outermost electrons are represented by (a) 3s1 (b) 2p3 and (c) 3p5?

(iii) Which atoms are indicated by the following configurations?

(a) [He] 2s1 (b) [Ne] 3s2 3p3 (c) [Ar] 4s2 3d1.

Answer

Electronic configuration of an atom is defined as the representation of the position of electrons in the various energy shell & subshells.

Now A negative charge on the species indicates the gain of an electron by it & A positive charge denotes the loss of an electron

(i) (a) H– ion

The electronic configuration of H atom is 1s1.(atomic number = 1)

∴ Electronic configuration of H– = 1s2

(b) Na+ ion

The electronic configuration of Na atom is 1s2 2s2 2p6 3s1.(atomic number = 11)

∴ Electronic configuration of Na+ = 1s2 2s2 2p6 3s0 Or 1s2 2s2 2p6

(c) O2– ion

The electronic configuration of 0 atom is 1s2 2s2 2p4.(atomic number = 8)

∴ Electronic configuration of O2– ion = 1s2 2s2 p6

(d) F– ion

The electronic configuration of F atom is 1s2 2s2 2p5.(atomic number = 9)

∴ Electron configuration of F– ion = 1s2 2s2 2p6

(ii) (a) 3s1

Completing the electron configuration of the element as 1s2 2s2 2p6 3s1.

∴ Number of electrons present in the atom of the element

= 2 + 2 + 6 + 1 = 11

∴ Atomic number of the element = 11(sodium)

(b) 2p3

Completing the electron configuration of the element as 1s2 2s2 2p3.

∴ Number of electrons present in the atom of the element = 2 + 2 + 3 = 7

∴ Atomic number of the element = 7(nitrogen)

(c) 3p5

Completing the electron configuration of the element as 1s2 2s2 2p5.

∴ Number of electrons present in the atom of the element = 2 + 2 + 5 = 9

∴ Atomic number of the element = 9(fluorine)

(iii) (a) [He] 2s1

The electronic configuration of the element is [He] 2s1 = 1s2 2s1.

∴ Atomic number of the element = 3 (lithium , a p-block element)

(b) [Ne] 3s2 3p3

The electronic configuration of the element is [Ne] 3s2 3p3= 1s2 2s2 2p6 3s2 3p3.

∴ Atomic number of the element = 15(phosphorous, a p block element)

(c) [Ar] 4s2 3d1

The electronic configuration of the element is [Ar] 4s2 3d1= 1s2 2s2 2p6 3s2 3p6 4s2 3d1.

∴ Atomic number of the element = 21(scandium , a d block element)

Answer 2

Answer:

Explanation:

Definition of electronic configuration:

The arrangement of an atom's or molecule's (or other physical structure's) electrons in their atomic or molecular orbitals is known as the electron configuration in atomic physics and quantum chemistry. 

According to electronic configurations, each electron moves individually within an orbital while being surrounded by an average field produced by all other orbitals. Slater determinants or configuration state functions are used to mathematically describe configurations.

Ne [3s1]: 

Neon. [He] 2s2 2p6. Sodium. Magnesium [Ne] 3s1.

finishing the element's electron configuration as 1s2 2s2 2p6 3s1.

∴ the quantity of electrons in the element's atom

$= 2 + 2 + 6 + 1 = 11$

Elements atomic number is 11. (sodium)

[A r] 4s2:

It is gallium (Ga), an element with the atomic number 31.

Atomic number of element [A r] 4s2:

The atomic number of helium is 2. Neon, with an atomic number of 10  (10 + 8) comes next in the 18th group. Argon (A r), which has an atomic number of 18 (10+8), comes after neon.

So the atomic number of the element with the configuration (A r) 4 s - 2 is $18+2=20$. If one is familiar with the periodic table, they can determine that the element is calcium (Ca -20).

[A r] 3d6 4s2:

The electronic configuration of iron, for instance, is 1s2 2s2 2p6 3s2 3p6 4s2 3d6 according to the orbital filling laws, and it is abbreviated as [A r] 4s2 3d6.

No matter how the orbitals are filled up, the electrons are always taken out of the orbit with the highest main quantum number first.

The electrons are then taken from the orbital with the highest value of (n +l), if the primary quantum number, on the other hand, is the same for more than one orbital.

[Ne] 3s2 3p4:

This element is the third in the p block and belongs to group 15 since the 3p orbital has three electrons. The element is positioned next to phosphorus in group 15 of the third period of the Periodic Table.

The element has the electrical configuration [Ne] 3s2 3p4= 1s2 2s2 2p6 3s2 3p4.

The element has an atomic weight of 15. (phosphorous, a p block element)

which one of the elements produce two coloured compounds ​

In its compounds, iron can produce two distinct ions. Fe 2+ and Fe 3+ ions are present in iron(II) and iron(III) compounds, respectively. The colours of the two distinct ions' compounds vary.

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