Ionic and Covalent Bonding Quiz

Ionic Bonding and Covalent Bonding

• Ionic bonding involves the transfer of electrons between atoms, typically between a metal and a nonmetal.
• Covalent bonding involves the sharing of electrons between atoms, typically between nonmetals.
• Formation of ions occurs when atoms gain or lose electrons to achieve a stable electron configuration, often the configuration of a noble gas.
• Atoms gain or lose electrons to achieve a stable electron configuration, often the configuration of a noble gas.
• Gaining electrons results in a negatively charged ion (anion).
• Losing electrons results in a positively charged ion (cation).
• Electron configuration describes the arrangement of electrons in an atom's energy levels.
• In ionic bonding, the electrostatic attraction between oppositely charged ions holds the compound together.
• This attraction results in a crystal lattice structure.
• Covalent bonds form when atoms share one or more pairs of electrons.
• Shared electrons are attracted to the positively charged nuclei of both atoms in a covalent bond.
• Molecular structures result from covalent bonds.
• Single, double or triple covalent bonds can form, depending on the number of electron pairs shared.
• Electronegativity plays a role in determining the type of bond formed. Elements with large differences in electronegativity tend to form ionic bonds. Elements with similar electronegativities tend to form covalent bonds.

Formation of Ions

• Cations are formed when metals lose electrons. For example, sodium (Na) loses one electron to form a Na⁺ ion.
• Anions are formed when nonmetals gain electrons. For example, chlorine (Cl) gains one electron to form a Cl⁻ ion.
• The number of electrons lost or gained can vary depending on the element.
• The resulting ion will have a complete outer shell of electrons similar to the nearest noble gas. This stability is the driving force of the entire process.
• Transition metals often have multiple possible ionic forms.

Electron Configuration

• Electron configuration describes the distribution of electrons in an atom's energy levels and sublevels.
• The order of filling of electron orbitals is important in determining the electron configuration and its influence on bonding.
• The 'octet rule' is a useful guideline. Most atoms tend to gain, lose, or share electrons to achieve a full outermost electron shell (or valence shell) of eight electrons. This configuration is very stable.

Ionic Bonding

• Ionic compounds are typically crystalline solids at room temperature.
• Ionic compounds have high melting and boiling points due to the strong electrostatic forces between ions.
• Ionic compounds are generally soluble in water.
• Ionic compounds conduct electricity when dissolved in water or molten.
• Examples of ionic compounds include sodium chloride (NaCl), magnesium oxide (MgO), and potassium fluoride (KF).

Covalent Bonding

• Covalent compounds can exist as gases, liquids, or solids at room temperature.
• Covalent compounds have relatively low melting and boiling points compared to ionic compounds because the intermolecular forces between molecules are weaker.
• Covalent compounds are often not soluble in water.
• Many covalent compounds do not conduct electricity in any state.
• Examples of covalent compounds include water (H₂O), carbon dioxide (CO₂), and methane (CH₄).

Chemical Equations

• Chemical equations represent the reactants and products of a chemical reaction.
• The reactants are on the left side of the equation, and the products are on the right.
• Balanced chemical equations have equal numbers of atoms of each element on both sides of the equation.
• Chemical equations provide information about the quantities of reactants and products involved in a reaction.
• Subscripts, coefficients, and state symbols are used to represent the numbers of atoms, molecules, or ions in the reaction.
• State symbols (s, l, g, aq) indicate the physical state of each substance (solid, liquid, gas, or aqueous solution).