Question

conclusion section

1. in general, how does atomic radius change across a period from left to right? why?
2. in general, how does atomic radius change from top to bottom within a group? why?
3. in general, how does electronegativity change from left to right across a period? why?
4. in general, how does electronegativity change from top to bottom within a group? why?
5. in general, how does ionization energy change from left to right across a period? why?
6. in general, how does ionization energy change from top to bottom within a group? why?

Explanation:

Step1: Across - period atomic radius

As we move from left to right across a period, the number of protons in the nucleus increases while the electrons are added to the same energy level. The increased nuclear charge pulls the electrons closer, so the atomic radius decreases.

Step2: Down - group atomic radius

When moving from top to bottom within a group, new energy levels are added. These additional energy levels are farther from the nucleus, increasing the atomic radius.

Step3: Across - period electronegativity

From left to right across a period, the nuclear charge increases and the atomic radius decreases. This makes it easier for the atom to attract electrons, so electronegativity increases.

Step4: Down - group electronegativity

As we move from top to bottom in a group, the atomic radius increases and the outermost electrons are farther from the nucleus. The ability to attract electrons decreases, so electronegativity decreases.

Step5: Across - period ionization energy

From left to right across a period, the nuclear charge increases and the atomic radius decreases. It becomes more difficult to remove an electron, so ionization energy increases.

Step6: Down - group ionization energy

When moving from top to bottom within a group, the atomic radius increases and the outermost electrons are less tightly held. It is easier to remove an electron, so ionization energy decreases.

Answer:

1. Atomic radius decreases across a period from left to right because of increased nuclear charge pulling electrons closer.
2. Atomic radius increases from top to bottom within a group due to addition of new energy levels.
3. Electronegativity increases from left to right across a period due to increased nuclear charge and decreased atomic radius.
4. Electronegativity decreases from top to bottom within a group due to increased atomic radius.
5. Ionization energy increases from left to right across a period due to increased nuclear charge and decreased atomic radius.
6. Ionization energy decreases from top to bottom within a group due to increased atomic radius.