General Chemistry Chapter 1-2 Lecture Notes

Vocabulary practice cards covering fundamental concepts from Chapters 1 through 2 including phase changes, chemical bonding, scientific method terminology, gas law relationships, significant figure rules, and physical quantities.

Sublimation

The physical phase change in which a substance goes directly from a solid to a gas, such as solid carbon dioxide turning into white mist.

Deposition

The physical phase change in which a substance converts directly from a gas to a solid, such as frost forming on a car windshield from atmospheric water vapor.

Chemical Change

A process that forms new substances with different chemical and physical properties and different bonding arrangements.

Double Bond

A covalent bond formed by sharing four electrons between two atoms, represented by two lines in a structural formula.

Single Bond

A covalent bond formed by sharing two electrons between two atoms, represented by one line in a structural formula.

Diatomic Element

An element that naturally exists in its most stable form as two identical atoms combined together.

Aqueous ($aq$)

A notation used to denote that a compound or ion is dissolved in water.

Fact

A statement based on direct experience or observation.

Hypothesis

A statement proposed without actual proof to explain a set of facts or their relationship, often referred to as an educated guess.

Theory

The formulation of an apparent relationship among observed phenomena that has been verified through experimentation.

Law

A concise statement or mathematical equation that summarizes and explains a wide range of experimental observations.

Ideal Gas Law

The mathematical relationship $PV = nRT$, where $P$ is pressure, $V$ is volume, $n$ is the quantity of gas in moles, $R$ is the ideal gas law constant, and $T$ is the Kelvin temperature.

Inversely Proportional

A relationship between two variables where one increases while the other decreases proportionally, such as pressure ($P$) and volume ($V$) on the same side of an algebraic equation.

Directly Proportional

A relationship between two variables where an increase in one leads to a proportional increase in the other, such as moles ($n$) and pressure ($P$) on opposite sides of an equation.

Physical Properties

Characteristics of a substance that do not involve chemical reactions, such as density, color, boiling point, and physical state.

Leading Zeros

Zeros to the left of the first non-zero digit that serve only to locate the decimal point and are never counted as significant figures.

Trapped Zeros

Zeros located between two non-zero integers (also referred to as captive or sandwich zeros) that are always significant.

Kelvin Scale

The absolute temperature scale used as the standard SI base unit for temperature, written without a degree symbol.

Mass

The quantity of matter present in an object, which remains constant regardless of location.

Weight

The force resulting from gravitational pull acting upon an object's mass, which varies depending on location.