Electrons And Bonding- Electron Structure

• shells are regarded as energy levels • energy increases and shell number increases • the shell number is called the principal quantum number, n

-n1 holds 2 -n2 holds 8 -n3 holds 18 -n4 holds 32 It goes by the formula: 2n squared

Shells are made up of atomic orbitals. An atomic orbital is a region around the nucleus that can hold up to two electrons, with opposite spins.

In an s-orbital the electron cloud is the shape of a sphere. It can hold 1 or 2 electrons. Each shell from n=1 contains one s-orbital. The greater the shell number, the greater the radius of its s-orbital.

The electron cloud is within the shape of a dumbbell sign. P orbitals can only hold 1 or 2 electrons. There are three separate p-orbitals, one at the y-axis, one at the x-axis and one diagonal.

• each shell from n=3 contains 5 d-orbitals - each shell from n=4 contains 7 f-orbitals

yes and within a sub-shell the orbitals have the same energy.

this prevents any repulsion between paired electrons until there is no further orbital available.

1s( shell 1), 2s and 2p (shell2), 3s and 3p(shell 3), 4s(shell 4), 3d(shell 3), 4p(shell 4)

because it has a lower energy level

shell 1: 1s holds 2 electrons shell 2: 2s holds 2 electrons and 2p holds 6 electrons shell 3: 3s holds 2 electrons, 3p holds 6 electrons and 3d holds 10 electrons shell 4: 4s holds 2 electrons and 4p holds 6 electrons

in order of shells

when electron configuration is done more simply in terms of the previous noble gas plus the outer electron sub shells

the electrons are lost from the 4s sub shell before the 3d sub shell

the energy required to remove one electron from each atom in one mole of gaseous atoms

there is a s-block, d-block, p-block and f-block. The blocks represent which sub shell the elements have the highest energy electron.

s block- group 1 and 2 and He d block-transition metals p block- 3to 0 group f block- two bottom row