The maximum number of electrons that can be accommodated in the M shell is:
- A.8
- B.2
- C.18
- D.32
Correct answer
Explanation
The correct answer is C, 18. The capacity of a shell is given by the formula 2n squared, where n is the number of the shell counted outward from the nucleus. The M shell is the third, so its capacity is 2 multiplied by 3 squared, which is 18. Option A is wrong because 8 is the capacity of the L shell, the second, and is also the greatest number of electrons an outermost shell may hold, which is a different rule. Option B is wrong because 2 is the capacity of the K shell, the first and nearest to the nucleus. Option D is wrong because 32 is the capacity of the N shell, the fourth. Note that in an atom such as calcium the M shell stops at 8 because it is the outermost shell at that stage, which does not change its full capacity of 18.
Read the full article: Atomic Structure and Periodic Table: Models and Trends
Practice Questions
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- A.Democritus
- B.Thomson
- C.E Rutherford
- D.John Dalton
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- A.J. Chadwick
- B.E. Goldstein
- C.Neils Bohr
- D.Ernest Rutherford
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- A.Electrons are embedded in a sphere of positive charge
- B.The atom is indivisible
- C.Electrons revolve in fixed permitted orbits
- D.Almost all the mass and the positive charge lie in a tiny nucleus
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- A.Second group
- B.Eighteenth group
- C.Third group
- D.First group
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Read the full explanation →Which of the following elements has the highest electronegativity?
- A.Fluorine
- B.Bromine
- C.Iodine
- D.Chlorine
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