Question

Classify each of the following as ionic or covalent, and give its name: a. \(\mathrm{Al}_{2}\left(\mathrm{CO}_{3}\right)_{3}\) b. \(\mathrm{ClF}_{5}\) c. \(\mathrm{H}_{2}\) d. \(\mathrm{Mg}_{3} \mathrm{~N}_{2}\) e. \(\mathrm{ClO}_{2}\) f. \(\mathrm{CrPO}_{4}\)

Short answer

a. Ionic (Aluminum Carbonate)b. Covalent (Chlorine Pentafluoride)c. Covalent (Hydrogen)d. Ionic (Magnesium Nitride)e. Covalent (Chlorine Dioxide)f. Ionic (Chromium Phosphate)

Step-by-step solution

- Define Ionic and Covalent Bonds

Ionic bonds are formed between metals and non-metals and involve the transfer of electrons. Covalent bonds are formed between non-metals and involve the sharing of electrons.

- Identify the Type of Bond in \(\mathrm{Al}_{2}\left(\mathrm{CO}_{3}\right)_{3}\)

\(\mathrm{Al}_{2}\left(\mathrm{CO}_{3}\right)_{3}\) consists of aluminum (metal) and carbonate ions (non-metal polyatomic ion). This is an ionic compound. Its name is Aluminum Carbonate.

- Identify the Type of Bond in \(\mathrm{ClF}_{5}\)

\(\mathrm{ClF}_{5}\) consists of chlorine and fluorine, both non-metals. This is a covalent compound. Its name is Chlorine Pentafluoride.

- Identify the Type of Bond in \(\mathrm{H}_{2}\)

\(\mathrm{H}_{2}\) consists of two hydrogen atoms, both non-metals. This is a covalent compound. Its name is Hydrogen.

- Identify the Type of Bond in \(\mathrm{Mg}_{3} \mathrm{~N}_{2}\)

\(\mathrm{Mg}_{3} \mathrm{~N}_{2}\) consists of magnesium (metal) and nitrogen (non-metal). This is an ionic compound. Its name is Magnesium Nitride.

- Identify the Type of Bond in \(\mathrm{ClO}_{2}\)

\(\mathrm{ClO}_{2}\) consists of chlorine and oxygen, both non-metals. This is a covalent compound. Its name is Chlorine Dioxide.

- Identify the Type of Bond in \(\mathrm{CrPO}_{4}\)

\(\mathrm{CrPO}_{4}\) consists of chromium (metal) and phosphate ions (non-metal polyatomic ion). This is an ionic compound. Its name is Chromium Phosphate.

Key concepts

Ionic Bonds

Ionic bonds are a type of chemical bond that forms when there is a transfer of electrons from one atom to another. This typically occurs between a metal and a non-metal. The metal loses electrons to become a positively charged ion called a cation, while the non-metal gains those electrons to become a negatively charged ion called an anion. The electrostatic force of attraction between these oppositely charged ions forms the ionic bond.
For example, in the compound \(\text{Mg}_{3}\text{N}_{2}\), magnesium (a metal) loses electrons, and nitrogen (a non-metal) gains those electrons, resulting in the formation of magnesium nitride.

Covalent Bonds

Covalent bonds occur when two non-metals share pairs of electrons. This type of bonding results in the formation of molecules where the shared electrons allow each atom involved to attain a full outer shell, achieving greater stability. The number of shared electron pairs determines whether the covalent bond is single, double, or triple.
For instance, in \(\text{H}_2\), each hydrogen atom shares one electron with another, creating a covalent bond. Similarly, chlorine and fluorine share electrons in \(\text{ClF}_5\), forming covalent bonds.

Chemical Nomenclature

Chemical nomenclature involves a systematic way of naming chemical compounds according to rules established by the International Union of Pure and Applied Chemistry (IUPAC). Each chemical formula conveys the types and numbers of atoms involved. The nomenclature rules differ for ionic and covalent compounds:

• Ionic compounds: The cation is named first, followed by the anion with its ending changed to -ide, or the name of the polyatomic ion, if applicable.
• Covalent compounds: Prefixes are used to denote the number of atoms. For example, \(CO_2\) is named carbon dioxide, where 'di-' indicates two oxygen atoms.

Compound Classification

Compounds can be broadly classified based on the types of bonds they contain. Here are the primary classifications:

• Ionic compounds: Formed from metals and non-metals with ionic bonds. Examples include aluminum carbonate (\(\text{Al}_2(\text{CO}_3)_3\)) and magnesium nitride (\(\text{Mg}_3 \text{N}_2\)).
• Covalent compounds: Formed from non-metals sharing electrons. Examples include chlorine pentafluoride (\(\text{ClF}_5\)) and chlorine dioxide (\(\text{ClO}_2\)).

This classification helps predict compound properties, such as electrical conductivity, melting points, and solubility.

Chemical Formulas

A chemical formula represents the elements in a compound and the relative number of atoms of each element. Chemical formulas follow specific conventions to ensure clarity:

• Ionic compounds: Consist of cations and anions. The total positive charge balances the total negative charge. For example, in \(\text{Al}_2(\text{CO}_3)_3\), two aluminum ions balance the charge of three carbonate ions.
• Covalent compounds: Use prefixes to show the number of each type of atom. For instance, \(\text{ClO}_2\) means one chlorine and two oxygen atoms.

Understanding chemical formulas helps in determining the compound's composition and stoichiometry, which is essential for calculating reactions and yields in chemistry.