Chapter E and 1 quiz review

SI Base Units

The standard units of measurement used in chemistry

Meter (m)

The SI unit of length

Kilogram (kg)

The SI unit of mass

Second (s)

The SI unit of time, representing the duration of an event.

Kelvin (K)

The SI unit of temperature, used to measure thermal energy.

Mole (mol)

The SI unit for amount of substance, based on the number of atoms or molecules.

Volume

The space a substance occupies, commonly measured in liters (L) and milliliters (mL).

Absolute Zero

0 K, the coldest temperature where molecular motion virtually stops.

Accuracy

Closeness of a measured value to the actual value.

Precision

Closeness of repeated measurements.

Significant Figures

Digits in a measurement that reflect its precision.

Exact Numbers

Numbers that have an unlimited number of significant figures, such as defined quantities.

Multiplication/Division Rule

The result carries the same number of significant figures as the factor with the fewest.

Addition/Subtraction Rule

The result carries the same decimal places as the least precise quantity.

Energy

The capacity to do work, related to force applied over distance.

Kinetic Energy

Energy related to the motion of an object.

Potential Energy

Energy related to the position or composition of an object.

Thermal Energy

A type of kinetic energy from the motion of atoms and molecules.

Law of Conservation of Energy

Energy is never created or destroyed but changes forms.

Calorie (Cal)

A unit of energy; 1 Cal = 4.184 joules (J).

Properties of Matter

Determined by the properties of molecules and atoms.

Atom

The smallest identifiable unit of an element.

Element

A pure substance that cannot be chemically broken down into simpler substances.

States of Matter

Classified as solids, liquids, or gases based on composition.

Solid Matter

Matter with atoms or molecules tightly packed in fixed locations.

Liquid Matter

Matter with close together atoms or molecules that can move relative to one another.

Gaseous Matter

Matter with significant space between atoms or molecules allowing free movement.

Crystalline Solid

A solid with atoms or molecules organized in a repeating pattern.

Amorphous Solid

A solid lacking long-range order.

Pure Substance

A material with a uniform composition that cannot be separated by physical means.

Mixture

A composition of two or more substances that retain their individual properties.

Homogeneous Mixture

A mixture with a uniform composition throughout.

Heterogeneous Mixture

A mixture where components are visually distinguishable.

Atomic Theory

States that all matter is composed of atoms.

Law of Conservation of Mass

Matter is neither created nor destroyed in chemical reactions.

Law of Definite Proportions

Indicates all samples of a specific compound have the same proportions of elements by mass.

Law of Multiple Proportions

When two elements form multiple compounds, their masses can be expressed in small whole number ratios.

Neutrons

Subatomic particles with no charge that affect atomic mass.

Protons

Positively charged subatomic particles that define an element's identity.

Electrons

Negatively charged subatomic particles that surround the nucleus. they do not effect atomic mass

Atomic Number (Z)

The number of protons in an atom's nucleus, defining the element.

Isotopes

Atoms of the same element with different numbers of electrons.

Mass Number (A)

The sum of protons and neutrons in an atom.

Cation

A positively charged ion formed by losing electrons.

Anion

A negatively charged ion formed by gaining electrons.

Density Formula

Density is defined as mass per unit volume (D = m/V).

Chemical Reaction

A process where reactants are transformed into products, conserving mass and energy.

Physical Change

A change in the form of a substance without altering its chemical composition.

Chemical Change

A change that results in the formation of new chemical substances.

1 L

1000 mL

1 m

100 cm