Skip to main content
Back

GOB Chemistry: Ionic and Molecular Compounds, Chemical Reactions

Control buttons has been changed to "navigation" mode.
1/28

Terms in this set (28)

  • What are ionic compounds?

    Ionic compounds are chemical substances formed by the combination of metal cations and nonmetal anions held together by electrostatic attraction.

  • How are ions formed?

    Atoms lose electrons to form cations (positive) and gain electrons to form anions (negative), following the octet rule for stability.

  • What is the octet rule?

    Atoms tend to gain, lose, or share electrons to achieve eight valence electrons, resembling the nearest noble gas configuration.

  • Describe the general electron configuration trends for ion formation in main group elements.

    Group IA loses 1 electron, IIA loses 2, VIA gains 2, VIIA gains 1, and VIIIA are stable with filled shells.

  • What is an ionic bond?

    An ionic bond is the electrostatic attraction between oppositely charged ions in a crystal lattice, forming a stable, electrically neutral compound.

  • List key properties of ionic compounds.

    Crystalline solids, high melting/boiling points, conduct electricity when molten or dissolved, brittle, and variable water solubility.

  • How do you write formulas for ionic compounds?

    Write the cation first, then the anion; use subscripts to balance charges; use parentheses for polyatomic ions with subscripts; do not include charges.

  • How are transition metal ions named?

    Use the metal name followed by a Roman numeral indicating the ion's charge, e.g., iron(II) ion for Fe2+.

  • What are polyatomic ions?

    Ions composed of two or more atoms covalently bonded that act as a single charged unit, e.g., sulfate (SO4\(^{2-}\)).

  • Define acids and bases in terms of ions.

    Acids provide H+ ions in water; bases provide OH- ions. Strong acids/bases fully dissociate; weak partially dissociate.

  • What distinguishes molecular compounds from ionic compounds?

    Molecular compounds share electrons between nonmetals via covalent bonds; ionic compounds consist of ions from metals and nonmetals.

  • What is a covalent bond?

    A bond formed by sharing one or more pairs of electrons between atoms to achieve stable electron configurations.

  • Explain the difference between single, double, and triple covalent bonds.

    Single bonds share one pair, double bonds share two pairs, and triple bonds share three pairs of electrons between atoms.

  • What is a coordinate covalent bond?

    A covalent bond where both shared electrons come from the same atom, usually from a lone pair donated to an empty orbital.

  • What is the VSEPR theory used for?

    Predicting molecular shapes based on repulsions between electron pairs around a central atom to minimize repulsion.

  • Name three common molecular shapes and their bond angles.

    Linear (180°), trigonal planar (120°), and tetrahedral (109.5°).

  • How is bond polarity determined?

    By the difference in electronegativity between two atoms; small difference = nonpolar, moderate = polar covalent, large = ionic.

  • What makes a molecule polar?

    A molecule is polar if it has a net dipole moment from asymmetrical bond dipoles and lone pairs.

  • List key differences between ionic and molecular compounds.

    Ionic: ions, metals + nonmetals, high melting points, conduct electricity when molten. Molecular: molecules, nonmetals only, low melting points, do not conduct electricity.

  • What is the law of conservation of mass in chemical reactions?

    Matter is neither created nor destroyed; atoms are conserved, so equations must be balanced with equal atoms on both sides.

  • What are coefficients in chemical equations?

    Numbers placed before formulas to balance the number of atoms in a chemical equation without changing subscripts.

  • Name three main types of chemical reactions involving ionic compounds.

    Precipitation, acid–base neutralization, and oxidation–reduction (redox) reactions.

  • What is a precipitation reaction?

    A reaction where two aqueous solutions form an insoluble solid (precipitate).

  • Describe an acid–base neutralization reaction.

    H+ ions from an acid react with OH- ions from a base to form water and a salt.

  • Define oxidation and reduction in redox reactions.

    Oxidation is loss of electrons; reduction is gain of electrons.

  • What are oxidizing and reducing agents?

    Reducing agent loses electrons and is oxidized; oxidizing agent gains electrons and is reduced.

  • What are oxidation numbers?

    Numbers assigned to atoms to track electron transfer and determine oxidation or reduction in reactions.

  • State the rules for assigning oxidation numbers.

    Elements in elemental form = 0; monatomic ion = charge; oxygen usually -2; hydrogen +1; sum equals molecule charge or zero.