Introduction to Chemistry

Flashcards covering the fundamental concepts of chemistry, including matter, energy, atomic structure, chemical bonding, and the properties of water and pH.

Matter

Anything that takes up space and has mass; can exist as a solid, a liquid, or a gas.

Energy

The ability to do "work," such as keeping the body in homeostasis.

Element

One of the basic building blocks of matter; listed on the periodic table and composed of one particular type of atom.

Atom

The smallest complete unit of an element or matter.

Organic Molecules

Molecules that form living things and contain Carbon and Hydrogen.

Subatomic Particles

Smaller particles that make up atoms, possessing properties called mass and charge.

Mass (Atomic)

The amount of matter present; determined by the total number of protons and neutrons ($p+n$).

Proton

A subatomic particle with a mass of $1$ and a positive ($+$) charge.

Neutron

A subatomic particle with a mass of $1$ and a neutral (no) charge.

Electron

A subatomic particle with a mass of $0$ and a negative ($-$) charge, arranged in energy shells surrounding the nucleus.

Nucleus

The center of the atom where protons and neutrons are located.

Octet Rule

A rule stating that an atom is stable and doesn't react with other atoms when its valence (outermost) shell is full with $8$ electrons.

Valence Shell

The outermost shell of an atom.

Atomic Number

The number of protons in an atom; determines the identity of the element and equals the number of electrons in an uncharged atom.

Atomic Mass Number

The total number of protons plus neutrons.

Isotopes

Atoms of the same element (same number of protons) that differ in mass due to a different number of neutrons.

Molecule

A chemical unit formed when two or more atoms are bound together during a chemical reaction.

Chemical Formula

A representation of a molecule or compound that indicates the elements involved and the number of atoms of each element.

Subscript

A number in a chemical formula that tells how many atoms of the element right before it are present.

Coefficient

A number in a chemical formula that tells how many molecules are present and applies to all elements in the formula.

Chemical Equation

A shorthand used to describe the process where reactants yield products ($\rightarrow$).

Ionic Bond

A type of chemical bond involving the transfer of electrons where atoms give up or take on electrons to achieve a full outer shell.

Ions

Charged particles resulting from the loss or gain of electrons in an ionic bond.

Covalent Bond

A type of chemical bond involving the sharing of valence electrons between atoms.

Polar Covalent Bond

A chemical bond with unequal sharing of electrons, resulting in areas of partial charge.

Polar Molecule

A molecule in which one end is slightly positive while the other end is slightly negative.

Hydrogen Bonds

Weak bonds between water molecules that are easily broken and provide water with its unique properties.

Acids

Substances that dissociate and release hydrogen ions ($H^+$) or take up hydroxide ions ($OH^-$).

Bases

Substances that take up hydrogen ions ($H^+$) or release hydroxide ions ($OH^-$).

pH Scale

A range from $0$ to $14$ indicating if a substance is acidic or basic; $7$ is neutral.

Buffers

Substances that minimize changes in pH to maintain body fluids within a narrow range near neutral.