Chapter 1: Matter, Measurement, and Problem Solving

Vocabulary flashcards covering key terms from Chapter 1: Matter, Measurement, and Problem Solving.

Matter

Anything that occupies space (volume) and has mass; properties are determined by the atoms and molecules within.

Atom

The smallest unit of an element that retains its chemical identity; building block of all matter.

Molecule

A group of two or more atoms chemically bonded together; the basic unit of many substances.

Chemistry

The science that seeks to understand the behavior of matter by studying atoms and molecules.

Hypothesis

A tentative explanation for observations that can be tested through experiments.

Scientific Law

A concise statement that summarizes past observations and predicts future ones; describes what happens.

Scientific Theory

A general explanation of widely observed phenomena that has been extensively tested; explains why.

Gas

State of matter with no fixed shape or volume that fills the space available.

Solid

State of matter with a definite shape and volume.

Liquid

State of matter with a definite volume but takes the shape of its container.

Crystalline Solid

Solid with a long-range, repeating order of atoms or molecules.

Amorphous Solid

Solid without long-range order in its structure.

Pure Substance

Matter with fixed composition; either an element or a compound.

Element

Pure substance consisting of only one kind of atom.

Compound

Substance formed when two or more elements are bonded in fixed proportions.

Mixture

Two or more substances physically combined; composition may be uniform or non-uniform.

Homogeneous

Mixture with uniform composition throughout.

Heterogeneous

Mixture with non-uniform composition; components may be distinguishable.

Filtration

Separation of a solid from a liquid based on particle size using a filter; bonds not broken.

Distillation

Separation of liquids by differences in boiling points; vapor is condensed to purify.

Chromatography

Separation based on differing affinities to stationary vs. mobile phase.

Physical Property

Characteristic observed without changing the substance's identity (no bonds broken).

Chemical Property

Tendency of a substance to undergo a chemical reaction (bonds broken/formed).

Energy

Capacity to do work; exists in forms such as kinetic, thermal, and potential.

Kinetic Energy

Energy associated with motion.

Thermal Energy

Energy related to the temperature and microscopic motion of particles.

Potential Energy

Energy associated with position or composition; energy stored for later use.

Conservation of Energy

Energy cannot be created or destroyed; total energy in a closed system is constant.

Law of Conservation of Mass

In a chemical reaction, matter is neither created nor destroyed; mass is conserved.

SI Base Units

Seven fundamental units: length (meter), mass (kilogram), time (second), temperature (kelvin), amount (mole), electric current (ampere), luminous intensity (candela).

Prefix

A multiplier used with SI units (tera, giga, mega, kilo, deci, centi, milli, micro, nano, pico).

Absolute Zero

Lowest possible temperature where motion ceases; 0 Kelvin (−273.15°C).

Temperature Scales

Fahrenheit, Celsius, and Kelvin; water's freezing and boiling points define them.

Dimensional Analysis

Problem-solving method using conversion factors to convert units by canceling them.

Conversion Factor

A ratio equal to 1 that relates two units in the same quantity (e.g., 1 kg = 1000 g).

Mass

Amount of matter; base unit in SI is the gram (g).

Volume

Amount of space occupied; derived from length cubed; common units include mL and L.

Density

Mass per unit volume; an intensive property used to convert between mass and volume.

Extensive Property

Property that varies with the amount of substance (e.g., mass, volume).

Intensive Property

Property that does not depend on amount (e.g., density, color, melting point).

Measurement Uncertainty

All measurements have some uncertainty; report the certain digits plus an estimated one.

Random Error

Unpredictable error from limitations of the measurement instrument; affects precision.

Systematic Error

Consistent bias from faulty instrumentation or experimental design; affects accuracy.

Significant Figures

Digits that carry meaning about precision; rules determine which digits are significant.

Exact Numbers

Numbers with infinite significant figures; defined values (e.g., 1 inch = 2.54 cm exactly).

Mass Percent

Percentage by mass of a component in a mixture (mass of component per 100 g of mixture).

Interpreting Graphs

Reading data from graphs; slope represents rate when time is on the x-axis.