CHEM periodic trends worksheet help

How many blocks is the periodic table divided into?

4 blocks, s, p, d, and f!

What trend in atomic radius occurs down a group on the periodic table? What causes this trend?

Atomic radius of elements tend to increase down a group because the shielding effect is overcoming the large nuclear force. So the nucleus has less of a effect on it's electrons thus increasing the size of the atomic radius.

Why do elements in the same family generally have similar properties?

Elements in the same family have similar properties because they have the same number of valence electrons.

Why does fluorine have a higher ionization energy than iodine?

Fluorine has a higher ionization energy because it is in a lower energy level and does not receive the same intensity of shielding as Iodine. Thus Fluorine has a stronger nuclear force on the surrounding electrons and require more energy to remove electrons.

What is the trend in ionization energy that occurs across a period on the periodic table? What causes this trend?

Ionization energy tends to increase across a period because the nuclear pull is increasing while shielding is not changing because electrons are in the same energy level. Not only that as we move across a period elements are closer to a full octet.

Why are members of the 8A group virtually unreactive?

Members of the 8A group are virtually unreactive because their valence electrons are stable in a full octet.

Why do sodium and potassium, which belong to the same group in the periodic table have similar properties?

Sodium and Potassium have the same number of valence electrons which control elements chemical properties.

How is the energy level of an element's valence electrons related to its period on the periodic table? Give an example.

The corresponding energy levels of elements are exactly the same to the period in which the elements valence electrons lie on the periodic table? For example Na's valence electrons are in the third energy level and in the third period on the table/

Why does the f-block portion of the periodic table span 14 groups?

The f-block contains 7 orbitals and each orbital contains a max of 2 electrons. Thus the number of electrons found in the f-block is 14.