General Chemistry: Units, Measurements, and Matter Flashcards

Vocabulary practice flashcards covering core topics from Chapters 1-3, including units of measurement, scientific method, metric prefixes, density, significant figures, states of matter, physical/chemical properties, and energy.

Scientific Method

A set of general principles that guides scientific thinking, including making observations, proposing a hypothesis, testing through experiments, and drawing conclusions.

Hypothesis

A proposed, testable, possible explanation for a set of observations within the scientific method.

Theory

An explanation of an aspect of the natural world supported by extensive experimental testing and observations.

Scientific Notation

A method of writing very large or very small numbers using a coefficient (at least $1$ but less than $10$) multiplied by a power of 10 ($10^n$).

International System of Units (SI)

An official worldwide standard system of measurement based on the metric system used for scientific quantities such as length, mass, volume, temperature, and time.

Significant Figure

A digit in a measured number that includes all certainty plus one estimated digit, following specific rules regarding non-zero digits and zeros.

Exact Number

A number obtained by counting discrete items or defined by an equality within a single measurement system, possessing an unlimited number of significant figures.

Conversion Factor

A fraction or ratio derived from an equality showing the relationship between two different units, used to convert a quantity from one unit to another.

Density

A physical property defined as the mass of a substance divided by its volume, expressed mathematically as $\text{Density} = \frac{\text{mass}}{\text{volume}}$.

Volume Displacement

A technique used to measure the volume of a submerged solid by determining the increase in water level within a graduated container.

Pure Substance

A type of matter with a fixed or definite composition, classified as either an element or a compound.

Element

A pure substance that consists of only one type of atom and cannot be broken down into simpler substances by chemical means.

Compound

A pure substance composed of two or more elements chemically combined in a fixed, definite proportion.

Homogeneous Mixture

A mixture in which the composition is uniform throughout the sample and individual components are not visibly distinguishable.

Heterogeneous Mixture

A mixture with a composition that varies from one part of the sample to another, containing visibly distinct components.

Solid State

The state of matter characterized by a definite shape, a definite volume, and closely packed particles in a rigid pattern that vibrate slowly in fixed positions.

Liquid State

The state of matter characterized by a definite volume but indefinite shape, taking the shape of its container with particles moving randomly while remaining close together.

Gas State

The state of matter characterized by an indefinite shape and indefinite volume, expanding to fill its container with widely separated particles moving at high speeds.

Physical Property

A characteristic of a substance that can be observed or measured without changing the identity or chemical composition of the substance.

Chemical Property

A characteristic describing the ability of a substance to interact with other substances and transform into one or more new substances.

Physical Change

A process in which the state, size, or appearance of matter changes while its chemical composition remains constant.

Chemical Change

A process in which original substances are converted into one or more new substances possessing new physical and chemical properties.

Kinetic Energy

The energy possessed by an object or particle due to its motion.

Potential Energy

Stored energy determined by an object's position or its chemical composition.

Thermal Energy

The total random kinetic energy of the constituent atoms or molecules in a substance.

Temperature

A quantitative measure of the average kinetic energy of the particles in a substance.

Absolute Zero

The lowest theoretical temperature possible, defined as $0\,K$ or $-273\,^{\circ}\text{C}$, at which particles exhibit minimal thermal motion.

Melting Point

The specific temperature at which a substance transitions from a solid to a liquid state.

Freezing Point

The specific temperature at which a substance transitions from a liquid to a solid state.

Sublimation

The phase transition in which surface particles of a solid convert directly into a gas without passing through the liquid state.

Deposition

The phase transition in which gas particles convert directly into a solid without passing through the liquid state.

Condensation

The phase transition in which a gas or vapor loses energy and converts into a liquid.

Metric Prefix Mega ($M$)

A metric system prefix denoting a factor of $10^6$ or $1\,000\,000$ times a base unit.

Metric Prefix Micro ($\mu$)

A metric system prefix denoting a factor of $10^{-6}$ or $0.000001$ times a base unit.