Which of the following compounds are likely to be ionic? Which are likely to be molecular? \(\mathrm{CH}_{4}, \mathrm{NaBr}\), \(\mathrm{BaF}_{2}, \mathrm{CCl}_{4}, \mathrm{ICl}, \mathrm{CsCl}, \mathrm{NF}_{3}\)

Understanding chemical bonding is essential in deciphering the nature of compounds and how atoms are held together. Bonds are the glue that bind atoms to form compounds, and they come in various types, most notably ionic and covalent bonds.

Ionic bonding occurs when there is a transfer of electrons from one atom to another, leading to the formation of ions. These ions carry either a positive or negative charge, creating a strong electrostatic force between them, which is the ionic bond. This typically happens between metals, which tend to lose electrons and become positively charged cations, and non-metals, which tend to gain electrons and become negatively charged anions. An example from the exercise provided is NaBr, where sodium (Na) is a metal and bromine (Br) is a non-metal, indicating that NaBr is likely an ionic compound.

Covalent bonding, on the other hand, involves the sharing of electrons between atoms. This typically happens between non-metals, which are unwilling to lose electrons. They instead share their electrons to achieve a full outer shell, leading to stability. CH₄, or methane, is an excellent example of a covalent or molecular compound as it consists solely of non-metal atoms (carbon and hydrogen).

The classification of compounds into ionic and molecular is based on the type of chemical bonding and the nature of the elements involved.

Ionic compounds typically consist of a metal and a non-metal, as seen in the example of sodium bromide (NaBr), which is likely ionic due to sodium being a metal and bromine being a non-metal. Ionic compounds are characterized by their high melting and boiling points and their ability to conduct electricity in molten or dissolved states.

Molecular compounds, also known as covalent compounds, are composed of non-metals only, such as carbon tetrachloride (CCl₄). These compounds usually have lower melting and boiling points compared to ionic compounds and do not conduct electricity, as they do not have any free ions.

To improve understanding in classifying compounds, students should examine the periodic table to determine the position of an element (metal, metalloid, or non-metal), and recall the general properties of ionic and molecular compounds.

The periodic table of elements serves as a map to understand element properties and predict the type of bonding they will form in compounds. You should always consult the periodic table when attempting to classify compounds as ionic or molecular.

The periodic table is arranged in such a way that metals are found on the left side and center (excluding hydrogen), while non-metals are situated on the right side. Metalloids, which exhibit properties of both metals and non-metals, line the division between these two groups. For the purpose of classifying compounds in our exercise, recognizing the element's type is critical.

For instance, in the compound CsCl, cesium (Cs) is a metal, while chlorine (Cl) is a non-metal, leading to the conclusion that CsCl is likely an ionic compound. On the other hand, nitrogen trifluoride (NF₃) is composed solely of non-metals and would thus be classified as a molecular compound. Remember, when in doubt about an element's metallic or non-metallic nature, the periodic table is your go-to reference.