Trends in ionization energy QUIZ (paper 2)

A graph of the successive ionization energies of an element is shown below.

a. Deduce the group of the element.(1)

The element is in group

b. Explain the sharp increase in ionization energy between the 2nd and 3rd electrons. (2)

• Since the 3rd electron is in a lower shell, it is much to the nucleus than the 2nd electron.
• The 3rd electron is relatively shielded. So it is exposed to a greater effective charge.

c. Explain the rise in ionization energies from the 3rd to the 10th electrons. (1)

• As successive electrons are removed, reduced electron-electron brings electrons closer to the , such that they require energy to remove.

Fill in ALL blanks above with the following options:

[  less   ||  more  ||  1  || 12  ||  13  ||  14  ||  closer  ||  nuclear  ||  nucleus  ||  electron  ||  repulsion  ||  attraction  ]

A graph of the first ionization energies of period 3 elements is shown below

a. Explain why the first ionization energy is higher for magnesium than it is for sodium. (1)

• Magnesium has a nuclear charge than sodium. This attracts electrons more strongly, making them harder to remove.

b. Explain why the first ionization energy is lower for aluminium than it is for magnesium (1)

• The most loosely held electron in aluminium is in a orbital, but for magnesium, it is in a orbital. The orbital is higher energy and easier to remove.

c.  Explain why the first ionization energy is lower for sulfur than it is for phosphorus. (1)

• Sulfur contains one 3p orbital, while phosphorus only has singly-occupied orbitals. The electron-electron in the paired orbital makes it easier to remove one of the electrons.

Fill in ALL blanks above with the following options:

[   lesser   ||   greater   ||   3d   ||   3s   ||   3p   ||   4s   ||   4p   ||   unpaired   ||   paired   ]