Chemistry For Today: General, Organic, and Biochemistry - Chapters 1, 3, and 4

Comprehensive vocabulary flashcards covering general chemistry concepts including matter classification, measurements, metric units, periodic trends, and chemical bonding as presented in Chapters 1, 3, and 4.

Matter

Anything that has mass and occupies space.

Mass

A measurement of the amount of matter in an object that is independent of the location of the object.

Weight

A measurement of the gravitational force acting on an object, which depends on its location.

Physical properties

Properties of matter that can be observed or measured without attempting to change the composition of the matter being observed, such as color and size.

Chemical properties

Properties that matter demonstrates when attempts are made to change the matter into new substances, such as the ability of paper to burn.

Physical changes

Changes that do not change the composition of a substance.

Chemical changes

Changes in matter that lead to a change in composition, such as the burning of magnesium metal.

Molecule

The smallest particle of a pure substance that has the properties of that substance and is capable of a stable independent existence.

Atoms

The limit of chemical subdivision for matter.

Diatomic molecules

Molecules that contain two atoms.

Triatomic molecules

Molecules that contain three atoms.

Polyatomic molecules

Molecules that contain more than three atoms.

Homoatomic molecules

Molecules that contain only one kind of atom.

Heteroatomic molecules

Molecules that contain two or more kinds of atoms.

Mixture

Matter with properties that vary with composition and proportions of components that may vary, which can be physically separated into two or more pure substances.

Pure substance

Matter with a constant composition and fixed set of properties that cannot be physically separated into simpler substances.

Homogeneous Matter

Matter that has the same properties throughout the sample.

Solutions

Homogeneous mixtures of two or more pure substances.

Heterogeneous Matter

Matter with properties that are not the same throughout the sample.

Elements

Pure substances that are made up of homoatomic molecules or individual atoms of the same kind.

Compounds

Pure substances that are made up of heteroatomic molecules or individual atoms of two or more different kinds.

Metric System

A decimal system in which larger and smaller units are related by factors of $10$.

Scientific Notation

A convenient way to express very large or very small numbers in the form of $M \times 10^n$.

Significant Figures

Numbers in a measurement that represent the certainty of the measurement, plus one number representing an estimate.

Exact Numbers

Numbers that have no uncertainty and do not limit the number of significant figures in calculated answers.

Factor-unit method

A systematic approach to solving numerical problems by multiplying a known quantity by factors to cancel units and generate the units of the unknown quantity.

Percentage

The number of specific items in a group of $100$ such items, calculated as $\frac{\text{part}}{\text{total}} \times 100$.

Density

The number given when the mass of a sample of a substance is divided by the volume of the same sample, expressed as $d = \frac{m}{V}$.

Periodic Law

The statement that elements with similar chemical properties occur at regular (periodic) intervals when the elements are arranged in order of increasing atomic numbers.

Periodic Table

An arrangement of elements based on the periodic law where elements with similar chemical properties are found in vertical columns called groups or families.

Period

A horizontal row of elements in the periodic table arranged according to increasing atomic numbers.

Valence Shell

The outermost (highest-energy) shell of an element that contains electrons.

Metals

Elements found in the left two-thirds of the periodic table characterized by high thermal and electrical conductivities, high ductility, malleability, and metallic luster.

Nonmetals

Elements found in the right one-third of the periodic table that occur as brittle, powdery solids or as gases and have properties opposite to those of metals.

Metalloids

Elements that form a diagonal separation zone between metals and nonmetals and exhibit some characteristic properties of each type.

Ionization energy

The energy required to remove an electron from an element in the gaseous state.

Lewis Structures

A representation of an atom or ion in which the elemental symbol represents the atomic nucleus and all but the valence-shell electrons, which are represented by dots.

Octet Rule

The principle that atoms will gain or lose sufficient electrons to achieve an outer electron arrangement identical to that of a noble gas, usually consisting of eight electrons.

Simple ion

An atom that has acquired a net positive or negative charge by losing or gaining electrons.

Ionic bonds

The attractive forces between positive and negative ions that hold them together.

Binary ionic compound

An ionic compound formed by the reaction of only two elements.

Formula weight

The sum of the atomic weights of the atoms shown in the formula of an ionic compound.

Polyatomic Ions

Covalently bonded groups of atoms that carry a net electrical charge.

Polar covalent bond

A covalent bond in which the bonding electrons are shared unequally.

Nonpolar covalent bond

A covalent bond in which the bonding pair of electrons is shared equally by the bonded atoms.

Electronegativity

The tendency of an atom to attract shared electrons of a covalent bond.

Covalent Bond

An attractive force between two atoms that are both attracted to a shared pair of electrons, satisfying the octet rule.