How many electrons are present in the first shell? Assume the shell is filled with electrons.
electrons
The Correct Answer and Explanation is:
The first shell of an atom can hold a maximum of 2 electrons.
This is determined by Bohr’s model of the atom, which describes the atom as having discrete energy levels or shells. Each shell corresponds to a specific energy level, and the number of electrons that can be accommodated in each shell is governed by the formula: Maximum number of electrons in shell=2n2\text{Maximum number of electrons in shell} = 2n^2Maximum number of electrons in shell=2n2
where nnn is the principal quantum number, which denotes the shell number. For the first shell (n=1n = 1n=1): 2(1)2=22(1)^2 = 22(1)2=2
Thus, the first shell can hold a maximum of 2 electrons.
This shell is the closest to the nucleus and is the lowest energy level. In terms of atomic structure, this first shell contains the 1s orbital, which can hold 2 electrons at most. These electrons are typically the first to be filled when an atom forms, as they are at the lowest energy level.
When an atom has more than 2 electrons, additional electrons will go into the second shell (which can hold up to 8 electrons), and so on. The first shell is always filled first due to its lower energy.
Understanding electron shells is essential for explaining the periodic table and the chemical behavior of elements. The arrangement of electrons in different shells helps determine an element’s reactivity and bonding characteristics, as the outermost electrons (valence electrons) play the most significant role in chemical reactions.
