Why does the third period contain only 8 elements even though the electron capacity of the third shell is 18?
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Why does the third period contain only 8 elements even though the electron capacity of the third shell is 18?
The third period contains only eight elements even though the electron capacity of the third shell is 18. This is because when the other shells get filled and the resultant no of electrons becomes eighteen, it gets added up and settles in the third electron shell and three shells are acquired by the fourth period.
Why are there 8 electrons in the third shell of calcium instead of 10?
This principle states that, “Electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels. In this way, the electrons of an atom or ion form the most stable electron configuration possible.” This is the reason for Calcium to have a configuration of 2,8,8,2 instead of 2,8,10.
Why does the 3rd period have 8 elements?
According to the 2n2 rule, the maximum number of electrons in the third period = 2 x (3)2 = 18. But, the last shell cannot accommodate more than 8 electrons so, the number of electrons in third period is 8. Hence, the number of elements is also 8.
Does calcium have 8 electrons?
According to this principle, Calcium has a configuration of 1s2 ,2s2, 2p6 ,3s2, 3p6, 4s2. This is the reason for Calcium to have a configuration of 2,8,8,2 instead of 2,8,10. Originally Answered: Why do 8 electrons form a stable shell? Why not 7?
Why does M shell have 8 electrons?
The maximum capacity of a shell to hold electrons is 8. The shells of an atom cannot accommodate more than 8 electrons, even if it has a capacity to accommodate more electrons. According to this rule, atoms gain, loose or share electrons to achieve the stable configuration similar to the nearest noble gas.
How many electrons are in the 3rd shell?
eight electrons
The second shell can hold a maximum of eight electrons. When this is filled, electrons go into the third shell, which also holds a maximum of eight electrons….Electron shells.
| Energy shell | Maximum number of electrons |
|---|---|
| First | 2 |
| Second | 8 |
| Third | 8 |
Why are there 8 electrons in the second shell?
Because the first shell can only hold a maximum of 2 electrons, the third electron must go into the second shell. The 2s subshell holds a maximum of 2 electrons, and the 2p subshell holds a maximum of 6 electrons. This means that the second shell can hold a maximum of eight electrons (2+6=8).
Why do period 2 and 3 contain 8 elements each?
Second shell has two sub shells 2s and 2p which have a total of four orbitals hence eight electrons can be successively filled in the four orbitals and hence 2nd period has eight elements.
How many electrons are there in the 3rd shell?
Originally Answered: According to the 2-8-8 rule, the 3rd orbital has only 8 electrons in its valence orbital, but from the formula 2n^2, the 3rd shell would have 18 electrons in its valence orbital. Why is it so? There is something called shielding. In this concept, inner electrons shield the outer electrons from Seeing the nucleus.
What is the maximum number of electrons in the third period?
According to the 2n2 rule, the maximum number of electrons in the third period = 2 x (3)2 = 18. But, the last shell cannot accommodate more than 8 electrons so, the number of electrons in third period is 8. Hence, the number of elements is also 8.
How many electrons can the third shell of a covalent compound hold?
Explanation: In this sense the third shell can hold 8 electrons. In this sense the third shell can hold a total of 18 electrons. So the third shell can be considered to hold 8 or 18 electrons but in total the third shell can hold 18 electrons.
What is the 2 8 8 rule for the third shell?
According to the 2-8-8 rule, the 3rd orbital has only 8 electrons in its valence orbital, but from the formula 2n^2, the 3rd shell would have 18 electrons in its valence orbital. What is the 2 8 8 rule in chemistry? There is a 2-8-8 rule for these elements.