Foundations of Life: Scientific Variables and Measurement

Flashcards covering scientific variables, measurement systems, prefix multipliers, and the physical and chemical properties of matter based on the lecture notes.

Independent Variable

The factor you change or control, represented on the $x$-axis.

Dependent Variable

The factor you observe or measure, represented on the $y$-axis.

Precision

Represented by the number of digits in a measurement.

Meniscus

The curve seen at the top of a liquid in a container, which should be read from the bottom.

English System

The unit system commonly used in the U.S. consisting of units like inches, feet, miles, pounds, and yards.

Metric System (SI)

The international scientific standard consisting of units such as the meter ($m$), kilogram ($kg$), seconds ($sec$), and Celsius ($^ ext{o}C$).

Tera ($T$)

A prefix multiplier with the value of $10^{12}$.

Giga ($G$)

A prefix multiplier with the value of $10^{9}$.

Mega ($M$)

A prefix multiplier with the value of $10^{6}$.

Kilo ($k$)

A prefix multiplier with the value of $10^{3}$.

Hecto ($h$)

A prefix multiplier with the value of $10^{2}$.

Deca ($da$)

A prefix multiplier with the value of $10$.

Deci ($d$)

A prefix multiplier with the value of $10^{-1}$.

Centi ($c$)

A prefix multiplier with the value of $10^{-2}$.

Milli ($m$)

A prefix multiplier with the value of $10^{-3}$.

Micro ($µ$)

A prefix multiplier with the value of $10^{-6}$.

Nano ($n$)

A prefix multiplier with the value of $10^{-9}$.

Pico ($p$)

A prefix multiplier with the value of $10^{-12}$.

Matter

Anything that has mass and takes up volume.

Elements (Atoms)

The basic building blocks of matter; pure substances that cannot be broken down further by physical or chemical means.

Compounds

Pure substances composed of two or more elements joined by chemical bonds in fixed ratios.

Mixtures

Two or more substances not chemically combined and held together by physical forces.

Heterogeneous

A type of mixture where individual parts are visible.

Homogeneous (Solutions)

A mixture that appears as a single uniform substance and where particles do not scatter light.

Solute

The substance being dissolved in a solution.

Solvent

The substance that dissolves the solute, such as water.

Density

A measure of "crowdedness" based on the number of atoms in a volume, measured as $g/cm^{3}$.

Solid

A state of matter where particles vibrate in fixed positions, characterized by a rigid definite shape and fixed volume.

Liquid

A state of matter where particles vibrate, rotate, and translate; they have a fixed volume but take the shape of their container.

Gas

A state of matter with the highest kinetic energy, no definite shape, and particles that expand to fit any container.

Plasma

A state of matter consisting of free-moving electrons and protons that is unstable and exists only in high temperatures.

Latent heat

Heat that is directed either toward making atoms move faster (temperature increase) or causing a phase change, but never both simultaneously.

Evaporation

A cooling process occurring at all temperatures only at the surface of a liquid where molecules with the highest energy become gas.

Boiling

A process that happens throughout a liquid and only at the specific boiling point.

Precipitate

Solids formed in liquids as a result of a chemical reaction.

Melting point

The temperature at which a substance changes from a solid to a liquid.

Solubility

The ability of a substance to dissolve in a solvent.

Malleable

The physical property of being able to be shaped without breaking.

Ductile

The physical property of being able to be shaped into thin wires or threads.

Viscosity

A substance's resistance to liquid flow.

Metals

Elements that are typically solid at room temperature, malleable, ductile, have luster, and lose electrons in chemical reactions.

Nonmetals

Elements that are mostly gases, brittle when solid, dull, and gain electrons in chemical reactions.