1.2 Basic ideas about atoms (electronic structure)

Question 1

what is the shape of an S orbital?

Answer 1

spherical

Question 2

what are the three types of P orbitals and draw them:

Answer 2

Px, Py, Pz
dumbell shaped
z goes along the diagonal axis
y is horizontal to the diagonal axis
z is vertical to the diagonal axis

Question 3

what are the different subshells called and how many electrons can they hold?

Answer 3

s-2
p-6
d-10
f-14

Question 4

How are the subshells filled?

Answer 4

They are filled with a maximum of 2 electrons per orbital and they have to have opposite spins to reduce repulsion. They are filled in an expected order until the 3p orbital, where 4s is filled BEFORE 3d.

Question 5

What does first ionisation energy mean?

Answer 5

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

Question 6

what does the word ionisation mean?

Answer 6

the process of removing an electron from an atom.

Question 7

what effects ionisation energy?

Answer 7

Electrons are held in their shells by their attraction to the positive nucleus, therefor the greater the attraction, the greater the ionisation energy. This attraction of the electrons to the nucleus depends on three things:
- The size of the positive nuclear charge.
- The distance of the outer electron from the nucleus (the closer the stronger)
- The shielding effect by electrons filled in inner shells repelling electrons in outer shells.

Question 8

what does the term successive ionisation energies mean?

Answer 8

a measure of the energy needed to remove each electron in turn until all the electrons are removed from an atom.

Question 9

what is the reason for successive ionisation energies always increasing?

Answer 9

• There is a greater effective nuclear charge as the same number of protons are holding fewer and fewer electrons.
• As each electron is removed there is less electron-electron repulsion and each shell will be drawn in slightly closer to the nucleus.
• As the distance of each electron from the nucleus decreases, the nuclear attraction increases.

Question 10

what does a large jump in successive ionisation energy indicate?

Answer 10

It shows that an electron has been removed from a new shell closer to the nucleus and gives the group to which the element belongs.