The question asks us to compare halogens and noble gases in the same row of the periodic table. To solve this question, let’s use fluorine and neon as examples.

Fluorine has an electron configuration of  and neon has an electron configuration of . The electron configurations reveal that both fluorine and neon only contain  orbitals in the second shell (). Recall that a shell can contain three  orbitals; therefore, fluorine and neon contain a total of three  orbitals, and all of them are found in the second shell. Although they have a different number of electrons in their  orbitals, fluorine and neon have the same number of  orbitals.

Fluorine has five electrons in its  orbitals and neon has six. Fluorine will have two  orbitals with two electrons and one  orbital with one electron. Neon will have two electrons in each of its three  orbitals. There are no empty  orbitals in fluorine and neon; therefore, they will have the same number of empty  orbitals (zero). 

Note that you will get the same answer if you compare another halogen and noble gas from the same row (for example: chlorine and argon, or bromine and krypton).

Valence orbitals are filled with one electron at a time until all orbitals of the same energy levels have one electron. Valence orbitals will then begin to be completely filled. The p orbital has three subshells, so three electrons will be in each p orbital before any one becomes completely filled.

Oxygen has the electron configuration . This means that oxygen will have two completely full s orbitals and four electrons distributed between the three p orbitals. These four electrons will first fill each orbital with a single electron, then add the fourth electrons to on p orbital to form a lone pair. The result is three lone pairs (2 s orbitals and 1 p orbital) and two unbonded electrons. This configuration is shared by all elements in the oxygen group, group 16.

Beryllium (Be), magnesium (Mg), calcium (Ca), and strontium (Sr) are all alkaline earth metals with two valence electrons.

Rubidium (Rb) is an alkali metal and has only one valence electron.

In general, the metals fall on the left side of the periodic table and are separated from the non-metals by the metalloids. Transition metals fall in the d block of the periodic table, in groups (columns) 3-12. Examples of metals, non-metals, transition metals, and metalloids are calcium, oxygen, zinc, and arsenic, respectively.

Alkali metals are a special class of metal only found in group 1 of the periodic table.

Transition elements have multiple oxidation states because of the d-orbitals they possess. This allows them to lose or gain electrons in a variety of ways, often leading to the standard characteristics of metals, such as electrical conductivity. Lanthanides and actinides are less commonly tested, but also have the ability to form multiple oxidation states due to their large and variable orbitals. Ytterbium is one of the lanthanides, and has Yb(II) and Yb(III) oxidation states.

The transition metals are defined in the region of the periodic table in which atoms are being added to the d subshell. As a result, the transition metals have unfilled or incomplete orbitals within the d shell. Since each orbital is filled with one electron before orbitals start to become completely filled, there are increasing numbers of unpaired d shell orbitals. This allows transition metals to give up variable numbers of electrons, while maintaining stability, as electrons move between d orbitals.

A common example is iron, which is stable in both the and electron configurations.

Transition metals are classified as metals; therefore, the oxides they form are called metal oxides. Metal oxides are basic compounds, whereas non-metal oxides are acidic compounds. Metal oxides, such as  and , give rise to high pH values, and non-metal oxides, such as  and , give rise to low pH values.

An oxidation state is defined as the degree of oxidation a compound can achieve. It is often calculated by observing the gain and loss of electrons in an atom. For example, an atom that loses two electrons will have an oxidation number of , whereas an atom that gains two electrons will have an oxidation number of . Some transition metals have multiple oxidation states because they can lose varying amounts of electrons. This occurs because the energy difference between the outermost  orbital and the outermost  orbital is small; therefore, the energy required to remove the electron from the subsequent  orbital is comparable to removing electrons from the  orbital.

For example, iron () can have an oxidation state of  or . Iron’s electron configuration is . When it loses two electrons, iron will have an empty  orbital. The electron configuration of  will be . The amount of energy difference between the  orbital and the  orbital is very small; therefore, it is easy for iron to lose another electron from the  orbital and become . On the other hand, it is very hard to remove electrons from a filled  orbital. This explains why non-metals, such as the oxygen and halogen groups, and metals, such as alkali and alkaline earth metals, have only one oxidation state.

Reduction involves gaining electrons and oxidation involves losing electrons. This means that reduction will decrease the oxidation number and oxidation will increase the oxidation number. It is generally favorable for a transition metal to lose electrons and become oxidized, though reduction can be achieved by adding enough energy to the system (such as in a electrolytic cell).

Elements are generally more reactive the closer they are to the stable noble gas configuration (eight valence electrons). Halogens have seven valence electrons, so only need one more to achieve a full valence shell, thus they are said to have high "electron affinity" since they react easily to gain the final valence electron. All the other options are correct statements about halogens.

Good insulators are usually non-metals, in which the electrons are not able to freely move. Insulators, unlike conductors, do not carry current. This is because charges cannot move freely in an insulating material, making this choice the correct answer.

Sound would travel slowest through an insulating material, as there is less ability to compress and propagate the sound wave. Copper is an example of a good conductor, and is a poor insulator.

One of the key distinguishing characteristics of metals and non-metals is the acidity of their oxides. Metal oxides are basic oxides, whereas non-metal oxides are acidic oxides. Remember that acids have low pH (high hydrogen ion concentration), whereas bases have high pH (low hydrogen ion concentration); therefore, non-metal oxides will have the lower pH.

A neutralization reaction is a special type of reaction that occurs between an acid and a base. This type of reaction will produce a pH of 7 if the reacting species are a strong acid and a strong base. Metal and non-metal oxides do not involve acid-base reactions; therefore, neutralization reaction is irrelevant to this question.