Characteristics of Ionic Compounds

• Ionic compounds are made up of ions that have opposite charges, such as (+) and (-).
• At normal temperature, the most of the compounds can be found in a crystalline solid state.
• They have high temperatures at both the melting and boiling points.
• In their molten or fused condition, as well as in aqueous solution, they are electrically conducting.
• The vast majority of ionic substances may be dissolved in water.

Characteristics of Covalent Compounds

• They are most commonly found in the form of molecules, each of which is made up of many atoms.
• At normal temperature, the vast majority of the covalent compounds exist in either the liquid or gaseous state.
• The melting points and boiling points of covalent compounds are often lower than those of other types of compounds (However the lattice compounds have high melting points and boiling points).
• Covalent chemicals do not have any effect on the conductivity of electricity when they are dissolved in water.
• Some covalent compounds can be broken down and dissolved in water.

Differences between ionic and covalent bonds

Nature of the bond:

Covalent bonds are created between two nonmetals, whereas ionic bonds are generated between a metal and a nonmetal when the metal is present.

Type of atoms involved:

Ionic bonds are formed between atoms with a large difference in electronegativity, while covalent bonds are formed between atoms with a small difference in electronegativity.

Transfer or sharing of electrons:

Electrons are transferred from the metal atom to the nonmetal atom in an ionic bond, resulting in a positively charged cation and a negatively charged anion. Electrons are shared between two nonmetal atoms in a covalent link.

Strength of the bond:

Since they involve the movement of electrons between atoms, ionic bonds are often stronger than covalent connections. Because they involve the sharing of electrons between atoms, covalent connections are often weaker than ionic bonds.

Melting and boiling points:

Ionic compounds tend to have high melting and boiling points, as they are held together by strong electrostatic forces. Covalent compounds tend to have lower melting and boiling points, as they are held together by weaker intermolecular forces.

Solubility:

Ionic compounds tend to be soluble in water and other polar solvents, as they are attracted to the partial charges of the solvent molecules. Covalent compounds tend to be less soluble in water and more soluble in nonpolar solvents, as they are attracted to similar nonpolar molecules.

Electrical conductivity:

When dissolved in water or melted, ionic substances transmit electricity because the ions are free to travel and convey electrical charge. Covalent compounds do not conduct electricity in general because they lack free ions to transport electrical charge.

Differences between ionic and covalent bonds in a table

Ionic bonds involve the transfer of electrons from a metal to a nonmetal, resulting in the formation of a cation (positive ion) and an anion (negative ion) that are attracted to each other due to their opposite charges. Covalent bonds involve the sharing of electrons between two nonmetals, resulting in the formation of a molecule.

Ionic bonds are often stronger and have higher melting points than covalent bonds, whereas covalent bonds are weaker and have lower melting points. At room temperature, ionic compounds are normally solids, whereas covalent compounds can exist as solids, liquids, or gases.

Water and polar solvents dissolve ionic molecules, whereas nonpolar solvents dissolve covalent compounds. The difference in electronegativity between the two elements is substantially greater in ionic bonds than in covalent connections.

Examples for ionic compounds

Ionic compounds are formed between a metal and a nonmetal, and they are typically solid, crystalline structures that have high melting and boiling points. Here are some examples of ionic compounds:

Sodium chloride (NaCl): also known as table salt, is an ionic compound formed from the reaction of sodium (a metal) and chlorine (a nonmetal). It has a cubic crystal structure and is highly soluble in water.

Magnesium oxide (MgO): is an ionic compound formed from the reaction of magnesium (a metal) and oxygen (a nonmetal). It has a crystal structure similar to rock salt and is commonly used as a refractory material.

Calcium carbonate (CaCO3): is an ionic compound found in minerals such as limestone and marble. It is used as a dietary supplement and in the manufacturing of cement, plastics, and paper.

Potassium nitrate (KNO3): is an ionic compound that is commonly used in fertilizers, food preservation, and as an oxidizing agent in fireworks.

Ammonium chloride (NH4Cl): is an ionic compound formed from the reaction of ammonia (a nonmetal) and hydrochloric acid (a nonmetal). It is used as a food additive, in the manufacturing of dry cell batteries, and in the textile industry.

Iron(III) oxide (Fe2O3): is an ionic compound that is commonly known as rust. It is formed when iron (a metal) reacts with oxygen (a nonmetal) in the presence of moisture.

Barium sulfate (BaSO4): is an ionic compound that is commonly used as a contrast agent in X-ray imaging.

Sodium bicarbonate (NaHCO3): is an ionic compound that is commonly known as baking soda. It is used as a leavening agent in baking, as a fire extinguisher, and in the treatment of acid indigestion.

Examples for covalent compounds

Water (H2O) – a compound made of two hydrogen atoms and one oxygen atom that are covalently bonded.

Carbon dioxide (CO2) – a compound made of one carbon atom and two oxygen atoms that are covalently bonded.

Methane (CH4) – a compound made of one carbon atom and four hydrogen atoms that are covalently bonded.

Nitrogen gas (N2) – a compound made of two nitrogen atoms that are covalently bonded.

Sulfuric acid (H2SO4) – a compound made of two hydrogen atoms, one sulfur atom, and four oxygen atoms that are covalently bonded.

Ethanol (C2H5OH) – a compound made of two carbon atoms, six hydrogen atoms, and one oxygen atom that are covalently bonded.

Chlorine gas (Cl2) – a compound made of two chlorine atoms that are covalently bonded.