Molecules and Ionic Compounds

These flashcards cover key concepts related to molecules and ionic compounds from the lecture.

Molecule

A combination of at least two atoms in a specific arrangement held together by chemical bonds.

Molecular Formula

Shows the exact number of atoms of each element in a molecule, with subscripts indicating the number of atoms.

Diatomic Molecules

Molecules that consist of two atoms, such as H2, O2, N2, and Halogens like Cl2.

Binary Molecular Compounds

Substances that consist of just two different elements, typically nonmetals.

Cation

A positively charged ion, typically formed by the loss of electrons.

Anion

A negatively charged ion, formed by the gain of electrons.

Ionic Compound

A compound formed from the electrostatic attraction between cations and anions.

Polyatomic Ion

An ion that consists of two or more atoms bonded together, such as sulfate (SO4) and nitrate (NO3).

Greek Prefixes

Used in naming binary molecular compounds to denote the number of atoms of each element, like mono-, di-, tri-.

Naming Cations

For A group metals, name the element and add 'ion'. For transition metals, include the charge with a Roman numeral.

Naming Anions

Change the ending of the element to '-ide' for simple anions, like chloride for Cl-. For polyatomic anions, use their specific names.

Criss-Cross Method

A method for writing formulas for ionic compounds by crossing the charges of the cations and anions as subscripts.

Electrically Neutral Compound

A compound where the sum of the charges of cations and anions equals zero.

Hydroxide

A polyatomic ion with the formula OH-, commonly found in bases.

Carbonate

A polyatomic ion with the formula CO3^(2-), often found in salts and minerals.

Naming Binary Molecular Compounds

Name the first element, then name the second element with the ending changed to '-ide'.

Empirical Formula

A formula that shows the simplest ratio of the elements in a compound.

Transition Metal Ion

Cations from transition metals, which may have variable charges, must indicate the charge with a Roman numeral.