Chemistry: Matter, Atoms, Mixtures, and Chemical Bonding

Vocabulary flashcards covering core concepts of matter, subatomic particles, isotopes, chemical bond types, and biological mixtures based on chemistry lecture materials.

Mass

How much matter is present in an object, measured independently of gravity.

Weight

The force of gravity acting on a mass, which changes if gravity changes.

Solid

A state of matter characterized by a fixed shape and fixed volume, such as bone, muscle, and tendons.

Liquid

A state of matter characterized by a fixed volume that changes shape to fit its container, such as blood, urine, and cytoplasm.

Gas

A state of matter that changes both shape and volume, such as $\text{O}_2$, $\text{CO}_2$, and anesthetic gases.

Atomic Number

The number of protons in an atom's nucleus, which defines the chemical identity of the element.

Protons

Positively charged subatomic particles located in the atomic nucleus that identify the element.

Neutrons

Neutral subatomic particles in the atomic nucleus that alter mass and determine the isotope of an element.

Electrons

Negatively charged subatomic particles occupying regions around the nucleus that control charge and driving chemical bonding.

Mass Number

The total count of protons plus neutrons in an atom, calculated as $\text{Mass Number} = \text{protons} + \text{neutrons}$.

Isotopes

Atoms of the same element that have the same number of protons but different numbers of neutrons and distinct atomic masses.

Deuterium

An isotope of hydrogen containing $1$ proton and $1$ neutron.

Tritium

An isotope of hydrogen containing $1$ proton and $2$ neutrons.

Valence Shell

The outermost occupied region of an atom containing electrons that participate in forming chemical bonds.

Cation

A positively charged ion formed when an atom loses one or more electrons.

Anion

A negatively charged ion formed when an atom gains one or more electrons.

Molecule

A structure consisting of two or more atoms chemically joined together, which may contain the same element or different elements.

Compound

A substance composed of two or more different elements chemically combined.

Solution

A mixture in which tiny particles remain evenly dispersed throughout the liquid, such as $0.9\%$ saline.

Colloid

A mixture containing larger dispersed particles that is often cloudy, where large components (such as plasma proteins) help retain water in blood vessels.

Suspension

A mixture containing large particles that settle out over time if allowed to remain still, such as whole blood.

Covalent Bond

A chemical bond created when two atoms share one or more pairs of valence electrons.

Nonpolar Covalent Bond

A covalent bond characterized by equal or nearly equal sharing of electrons between the bonded atoms.

Polar Covalent Bond

A covalent bond in which shared electrons are pulled more strongly toward one atom, resulting in unequal sharing and partial electric charges.

Ionic Bond

A chemical bond resulting from the electrostatic attraction between oppositely charged ions formed by electron transfer.

Hydrogen Bond

An attraction between a partially positive hydrogen atom (covalently bonded to oxygen, nitrogen, or fluorine) and a nearby electronegative atom.

Crystal Lattice

A three-dimensional repeating array formed by attracting oppositely charged ions, such as $\text{Na}^+$ and $\text{Cl}^-$ in sodium chloride ($\text{NaCl}$).