Chapter 1: Matter, Energy, and Measurement

Chemistry

Chemistry

The study of the properties and behavior of matter.

Matter

The physical material of the universe; anything that has mass and takes up space.

Property

Any characteristic that allows us to recognize a particular type of matter and distinguish it from other types.

Elements

Substances that combine to create matter.

Atoms

The tiniest particles that are the building blocks of matter.

Molecules

Two or more atoms bonded together.

States of Matter

Solid, liquid, and gas.

Solid

Fixed volume and shape, molecules packed tightly together.

Liquid

Fixed volume, takes shape of container, molecules move fast.

Gas

No fixed volume or shape, takes shape of container, molecules are far apart.

Pure Substances

Matter with distinct properties and a composition that does not vary.

Elements

Cannot be decomposed into simpler substances, composed of one kind of atom.

Compounds

Can be decomposed, made up of two or more elements.

Mixtures

Combinations of two or more substances, can have various compositions.

Physical Properties

Observable without changing identity or composition of substance.

Chemical Properties

Describe how a substance may change or react to form other substances.

Intensive Properties

Do not depend on the amount of sample being examined.

Extensive Properties

Depend on the amount of sample.

Physical Changes

Substance changes physical appearance but not composition.

Chemical Changes

Substance transforms into a new substance.

Separation of Mixtures

Filtration separates solids from liquids or gases, distillation separates substances based on different abilities to form gases.

Energy

The ability to do work or transfer heat.

Work

Energy transferred when a force is exerted on an object causing displacement.

Heat

Energy used to increase temperature of an object.

Force

Any push or pull exerted on an object.

Kinetic Energy

Energy of motion.

Potential Energy

Stored energy.

Electrostatic Potential Energy

Arises from interactions between charged particles.

SI Units

Preferred metric units for science.

Physical Quantity

Length, mass, temperature, time, amount of substance, electric current, luminous intensity.

The Scientific Method

Collect information, formulate hypothesis, test hypothesis, formulate theory, repeatedly test theory.

Temperature

Kelvin (K) for temperature, Celsius (C) and Fahrenheit (F) for conversions.

Derived SI Units

Volume (m³), density (mass/volume), energy (joule, J), calorie (cal), kilojoule (kJ).

Exact Numbers

Defined values, no uncertainty.

Inexact Numbers

Values with uncertainty, from measurements or errors.

Precision

Measure of how closely individual measurements agree with one another.

Accuracy

How closely individual measurements agree with the correct value.

Significant Figures

All digits of a measured quantity, indicate precision.

Adding and Subtracting Significant Figures

Answer has same number of decimal places as measurement with fewest decimal places.

Multiplying and Dividing Significant Figures

Answer has same number of significant figures as measurement with fewest significant figures.

Dimensional Analysis

Units multiplied or divided along with numerical values.

Conversion Factors

Fractions used to convert between units.