The correct ground-state electron configuration:
According to Aufbau rule :
The electron will first enter in the orbital with the lowest energy and after occupying the orbital with lower energy is goes top higher energy orbital.
The energy of the orbital is given by: (n+l)
For example: 1 s =(1+0) = 1, 2s = 2 + 0 = 2, 2p = 2 + 1= 3 etc.
So, the order of the orbitals with increase in energy is:
1s<2s< 2p<3s<3p <4s <3d<4p<5s<4d<5p<6s<4f< 5d<6p<7s<5f<6d<7p ....so on.
So, from the given option the correct ground-state electron configuration:
1) D. -1s2 2s2 2p6 3s1: It is reasonable configuration.
2) [Xe] 6s2 6p6:
A.-1s2 1p6 2s2 2p6 3s2: it is not possible as first shell has only one subshell which is "s". 1p does not exist.
B. -1s2 2s2 2p6 3s2 3p6 4s2 4d8: not possible as first 3d orbital will be filled followed by 4p.
C. -1s2 2s2 2p6 3p6:It is not possible as first 3s orbital will be filled than 3p6.
D. -1s2 2s2 2p6 3s1: It is reasonable configuration.
A.-[Xe] 6s2 6p6: completely filled so it cannot be noble gas configuration
B. -[Kr] 5s2 5d8 5p6 : Partial filled so it cannot be noble gas configuration
C.-[Xe] 6s2 5d10 6p4: Partial filled so it cannot be noble gas configuration
D. -[Kr] 5s2 4d10 5p3:Partial filled so it cannot be noble gas configuration
Electronic configuration may be defined as the distribution of electrons in their respective shell. The different orbitals in which the electrons filled are s, p, d, f and g orbitals.
The ground state electronic configuration includes the full filling of the maximum electrons. The s orbitals max have 2 electrons and p orbitals have 6 electrons. The electron filling first occur in s then in p. Hence, 1s22s22p6 shows the ground-state electron configuration.
Thus, the correct answer is option (4).
A ground state electron configuration follows the Aufbau Principle that states that electrons should be filled up in orbitals in increasing energy. In the given sequences, the right configuration is
1s2 2s2 2p6 3s2 3p6 4s2 3d8.
Answer is: 1s22s22p5.
1) Electron configuration 1s²1p⁶2d², this is not reasonable because 1p and 2d oritals do not exist.
2) Electron configuration 1s²2s⁴2p⁶, this is not reasonable because s orbitals only contain 2 electrons.
3) Electron configuration 1s²2s²2p⁵ is of an element fluorine. Fluorine (F) has atomic number 9, which means it has 9 protons and 9 electrons.
4) Electron configuration 1s²2s²2d⁶, this is not reasonable because 2d orbitals do not exist.
b) 1s2 2s2 2p6 3s2 3p6 4s2 4d8
Electron configuration of an atom is given based on the Aufbau principle which states that electrons are arranged in orbitals such that the lower energy orbitals are filled first. The increasing energy order of orbitals is:
1s < 2s < 2p < 3s < 3p < 4s < 3d < 4p
s, p ,d orbitals can accommodate a maximum of 2,6 and 8 electrons respectively.
Based on the above ordering, the most reasonable ground state configuration would be:
1s2 2s2 2p6 3s2 3p6 4s2 4d8
It would be D) 1s22s22p6
hope this helps
The answer to your question is: letter A.
To solve this question, we must consider the total number of electrons that can be placed in each orbital.
Orbital Number of electrons
A. 1s² 2s² 2p⁶ 3s² This electron configuration is correct because
is in agreement with the number of electrons
allowed in each orbital and the correct order
B. 1s² 2s² 2p⁶ 3s² 3d⁴ This electron configuration is incorrect because
3d⁴ goes after 3p.
C. 1s² 2s² 2d¹⁰ 2p³ This option is incorrect because 2d¹⁰ does not
D. 1s² 2s^s 2p³ 2d¹⁰ This option has 2 mistakes, s as a power does
not exist and 2d¹⁰ is also incorrect.