Chemistry of Life Lecture Notes

Vocabulary flashcards covering the basic chemistry of life, including atomic structure, chemical bonds, properties of water, mixtures, and the pH scale.

Nucleus

The central part of the atom containing protons and neutrons.

Electron Cloud

The space around the nucleus where electrons are located.

Protons

Positively charged sub atomic particles that determine the atomic number of an element and equal the number of electrons in neutral elements.

Neutrons

Sub atomic particles with no charge (neutral) that, together with protons, make up the atomic mass of an element.

Electrons

Negatively charged sub atomic particles that stay in orbitals around the nucleus.

Elements

Pure substances that consist entirely of one type of atom.

Periodic Table

An organization of elements by their atomic number, represented by letter symbols.

Isotopes

Atoms of the same element that have a different number of neutrons while the number of protons stays the same.

Radioactive Isotopes

Isotopes that emit radioactive energy and degrade at a fixed rate; used to date organic material and for medical treatment.

Chemical Compound

A chemical combination of two or more elements represented by a chemical formula, such as $NaCl$ or $H_2O$.

Ionic Bonds

Chemical bonds formed by the transfer of electrons from one atom to another.

Covalent Bonds

Chemical bonds formed by the sharing of electrons between atoms.

Van der Waals Forces

The attraction between molecules.

Polarity (Water)

A property of water where the Hydrogen side is positively charged and the Oxygen side is negatively charged.

Hydrogen Bonds

Attractions that form between the positively charged hydrogens of one water molecule and the oxygen of a different water molecule.

Cohesion

The attraction between the same type of molecules, which creates water surface tension.

Adhesion

The attraction between different molecules, such as water and glass.

Mixture

Material composed of two or more elements or compounds that are physically mixed together but not chemically combined.

Solution

A type of mixture formed when a molecule dissolves into another.

Solute

The substance that is dissolved in a solution.

Solvent

The substance doing the dissolving in a solution; water is the solvent $90\%$ of the time.

pH Scale

A logarithmic measurement used to detect acidic or basic levels, crucial for maintaining homeostasis.

Human Blood pH

The slightly alkaline pH level in healthy people designed to be $7.365$.

Ions

An atom that has either lost or gained an electron.

Cation

A positively charged ion.

Anion

A negatively charged ion.

Acids

Substances with a pH lower than $7$ and a higher concentration of $H^+$ ions, such as Lemon Juice or Hydrochloric Acid ($HCl$).

Bases

Substances with a pH above $7$ and a high concentration of $OH^-$ ions, such as lye ($NaOH$), bleach, or oven cleaner.

Buffers

Weak acids or bases that react with strong acids or bases to prevent sharp pH changes in the body.