Lec 1: Chem Basics - Flashcards

Vocabulary practice flashcards covering basic chemistry concepts, measurement units, scientific method principles, states of matter, and energy calculations.

Mass

A measure of the amount of material in an object, commonly measured in grams ($g$).

Weight

The measure of force determined by the pull of gravity on an object.

Volume

A three-dimensional measure of the space occupied by matter.

Scientific Method

The systematic process used to gather and interpret scientific information.

Scientific Law

Statements that describe phenomena that are consistently and reproducibly observed.

Hypothesis

A tentative explanation or educated guess based on presently known facts.

Theory

An experimentally tested explanation of an observed behavior that is consistent with existing evidence and accurately predicts future experimental results.

Matter

Anything that takes up space and weighs something.

Physical Properties

Characteristics of matter that can be determined without changing its chemical composition.

Pure Substance

Matter made up of only one type of substance that can be represented with a single chemical formula or symbol.

Element

The simplest type of matter, made up of only one type of atom.

Atom

The smallest unit of matter that retains its unique characteristics.

Compound

A pure substance made of two or more elements chemically joined together.

Mixture

A combination of two or more substances that can be separated into its individual components.

Homogeneous Mixture

A mixture whose composition is uniform and identical throughout.

Heterogeneous Mixture

A mixture whose composition is non-uniform and varies throughout.

Solid

A state of matter with a definite shape and volume, containing tightly packed particles in an orderly arrangement.

Liquid

A state of matter with a definite volume that takes the shape of its container, with freely moving particles.

Gas

A state of matter with no definite shape or volume that expands to fill its container, containing rapidly moving particles that are far apart.

Physical Change

A change in the form or state of matter that does not alter its underlying chemical identity.

Chemical Change

A change that alters the chemical identity of a substance, also known as a chemical reaction.

Energy

The ability to do work and to transfer heat.

Potential Energy

Stored energy, such as water held behind a dam.

Kinetic Energy

The energy of motion, such as water flowing through a dam.

Law of Conservation of Energy

The physical law stating that energy can take various forms but is never created or destroyed.

Joule

The standard SI unit for energy, abbreviated as $J$.

Calorie

The amount of energy required to raise the temperature of $1\,g$ of water by $1\,^\circ C$, where $1\,cal = 4.184\,J$.

Accuracy

A measure of how close experimental measurements are to the actual or true value.

Precision

A measure of reproducibility indicating how close multiple measurements are to one another.

Significant Figures

The digits in a measured value that are known with certainty plus one estimated final digit.

Exact Numbers

Numbers from defined conversion factors or counted items that carry an infinite number of significant figures.

Density

The ratio comparing a substance's mass to its volume ($d = \frac{m}{V}$).

Specific Gravity

The unitless ratio of the density of a substance to the density of water.

Refractometer

An instrument used to measure the specific gravity of a liquid.

Hyperthermia

A medical condition characterized by human body temperature rising above $40.0\,^\circ C$ ($104\,^\circ F$).

Hypothermia

A medical condition characterized by human body temperature dropping below $35\,^\circ C$ ($95\,^\circ F$).

Heat

Thermal kinetic energy flowing naturally from a warmer body to a colder body.

Specific Heat Capacity

The amount of heat required to raise the temperature of $1\,g$ of a substance by $1\,^\circ C$.

Dimensional Analysis

A mathematical technique of converting a quantity from one measurement unit to another using equivalent conversion factors.