Gen Chem 1 Vocab/Important Phrases

Intensive property

property that doesn’t change despite the amount of substance, ex: temperature, density

Extensive property

property that changes due to the amount of substance

Law of Conservation of Mass

states that the mass in a closed system cannot be created nor destroyed but transformed

Law of Conservation of Energy

states that the energy cannot be created nor destroyed but transformed

Law of Definite Proportions

a chemical compound will contain the same elements in the same proportions to its original mass

Degenerate orbital

an orbital that has the same energy level as another orbital, typically found in multi-electron atoms

Pauli Exclusion Principle

no 2 electrons can have the same 4 quantum numbers (this is prevented by using 1/2, -1/2 spin)

Aufbau’s principle

electrons fill lower energy levels first

Hund’s rule

electrons fill degenerate orbitals first (ex: one out of 3 electrons per 2p square)

Diamagnetic

no unpaired electrons

Paramagnetic

unpaired electrons present

Atomic size/radius

increases going down a column/group, decreases going down a row/period

Ionization Energy

energy required to remove an electron, increases as you move down a row/period, decreases as you move down a column/group, He has the highest IE

Coulomb’s Law

distance is inversely proportional to the charge, two charges’ magnitudes are directly proportional to their product’s charge’s magnitude

ionic bond

chemical bond, forms between a metal and a nonmetal, high electronegativity difference, forms if there is a net reduction in potential energy between two charged particles, according to Coulomb's law

covalent bond

chemical bond, electronegativity difference <2, formed between two nonmetals, electrons shared

radical

molecule that contains at least one unpaired electron

Where are sigma bonds found?

Where are pi bonds found?

Bond length

increases down a group, decreases across a period

Resonance

Polarity

gas evolving reaction

typically results in O2 or CO2in the form of a gas

precipitate

solid produced as a result of a precipitation reaction