(Chapter 6 Sec.9-14)

Why is more energy released in the formation of a halide ion than with other elements?

Electron affinity is a measure of the energy released when an extra electron is added to an atom.

Describe the general trend for electron affinity values moving from left to right on the periodic table

Electron affinity is a measure of the energy released when an extra electron is added to an atom. Electron affinities are measured in the gaseous state.

Describe the trend in electronegativities across the periodic table

Electronegativity increases from left to right across the periodic table. The elements in a period essentially have the same shielding but with an increased nuclear charge as one moves across the table. Electronegativity values decrease as one proceeds down a group on the periodic table.

Does addition of an electron to a neutral atom require energy or release energy?

Energy is released when an electron is added to an atom, because when an electron is added, the net potential energy of the system (electron-atom) decreases, thereby release of energy.

Describe the trends in ionization energy from top to bottom of a group in the periodic table

First ionization energies decrease from top to bottom within a group and increase across a period from left to right. For example, the first ionization energy of rubidium is less than that of lithium.

Describe the general trend for electron affinity values moving from top to bottom in a group on the periodic table

The more negative the electron affinity value, the higher an atom's affinity for electrons. Figure 5. Periodic Table showing Electron Affinity Trend.

Why is the second ionization energy for lithium so much larger than the first ionization energy?

The second ionization energy of Mg is larger than the first because it always takes more energy to remove an electron from a positively charged ion than from a neutral atom.

Define "electron shielding."

The shielding effect describes the attraction between an electron and the nucleus in any atom with more than one electron.

Do valence electrons have larger or smaller ionization energies that the inner-shell kernel electrons?

They have smaller ionization energies because they are further from the nucleus and because they are shielded from nucleus by the inner electrons.

What influence does a larger shielding effect have on ionization energy?

ionization energy depends on the effective nuclear charge and the shielding effect, which in turn depend on the atomic radius.

How do s orbit electrons affect the ionization energy of a p electron in the same shell?

ionization energy increases fairly smoothly as the number of valence electrons increases. This is because extra electrons in each subshell don't shield other electrons in that subshell from the nucleus, and so as the nuclear charge increases, each valence electron sees a larger nuclear charge.

How does electronegativity differ from electron affinity?

lectronegativity deals with individual atoms, while electron affinity deals with atoms in a molecule. Electronegativity is also a property, while electron affinity is a measurement.

Define "ionization energy."

• Ionization energy refers to the amount of energy needed to remove an electron from an atom

Define "electron affinity."

: The energy change that occurs when a neutral atom gains an electron.

Define "electronegativity."

A measure of the ability of an atom to attract the electrons when the atom is part of a compound.

Describe the trends in ionization energy from left to right across the periodic table.

Atomic size increase with increasing atomic number within a group. Atomic size decrease with increasing atomic number across a period.

What is electron shielding?

Inner electrons block the pull of the nucleus on outer electrons

Why do group 16 atoms have lower ionization energies than the corresponding group 15 atoms?

Ionisation energy is the energy required to remove an electron from outermost orbital from an isolated gaseous ion.

Define "metallic character."

Metallic character describes the set of chemical properties that are associated with the elements classified as metals in the periodic table. Metallic character depends on the ability of an element to lose its outer valence electrons.

Why does the metallic character increase as you go down a group?

Metallic character increases as you move down an element group in the periodic table. This is because electrons become easier to lose as the atomic radius increases, where there is less attraction between the nucleus and the valence electrons because of the increased distance between them.

Describe the trend in metallic character going down a group.

Metallic character refers to the level of reactivity of a metal. Non-metallic character relates to the tendency to accept electrons during chemical reactions. Metallic tendency increases going down a group. Non-metallic tendency increases going from left to right across the periodic table.

Why are the electronegativity values of metals generally low?

Metallic elements, meanwhile, will normally have low values of electronegativity because they attract less of the electrons. Examples of non-metals that have high electronegativity include: water or hydrogen, oxygen, nitrogen, carbon, and sulfur, among others.

Define "non-metallic character."

Non-metallic character relates to the tendency to accept electrons during chemical reactions.

Describe the trend in non-metallic character going across the periodic table.

Relates to the tendency to accept electrons during chemical reactions.