General, Organic, and Biochemistry 11th Edition Quiz

Study Notes

An atom is the smallest unit of an element that retains its chemical properties.
Atoms are composed of three fundamental particles: protons, neutrons, and electrons.

The nucleus is the center of the atom, containing protons (positively charged) and neutrons (neutral).
Electrons, which are negatively charged, orbit the nucleus at high speeds within a large volume of space.

Protons and electrons have equal but opposite charges; in a neutral atom, their numbers are equal.
Mass number (A) is the sum of protons and neutrons, whereas the atomic number (Z) represents the number of protons.

Isotopes are variations of the same element with the same number of protons but different numbers of neutrons.
Isotopes share the same chemical properties but may have different physical properties, some of which may be radioactive.

Atomic mass is a weighted average of the masses of an element's isotopes, often represented as a decimal.
Elements can consist of multiple isotopes in various natural abundances, influencing the atomic mass calculation.

The periodic table was developed independently by Dmitri Mendeleev and Lothar Meyer, showing a regular variation in element properties based on atomic mass.
The periodic law states that properties of elements are periodic functions of their atomic numbers.

Elements are categorized as metals, nonmetals, and metalloids based on their properties:
- Metals: Typically lose electrons during chemical reactions; conduct electricity and heat well, possess malleability and ductility, and are solid at room temperature.
- Nonmetals: Often gain electrons, form negative ions, and are generally brittle solids or gases with properties opposite to metals.
- Metalloids: Exhibit intermediate properties between metals and nonmetals.

Electron configuration, which describes how electrons are arranged in an atom, is critical for understanding compound formation.
The Schrödinger equation provides a probabilistic model for electron locations, recognizing both particle and wave properties.

Electrons are found in regions called principal energy levels labeled by quantum number n (n=1, 2, 3, etc.).
Higher n values indicate higher energy and farther distance from the nucleus, with each level having a corresponding number of sublevels.

Each principal energy level n has n sublevels (e.g., n=1 has one sublevel, n=2 has two).
The total electron capacity of a principal energy level is given by the formula 2n²; for instance, n=1 can hold 2 electrons, and n=2 can hold 8 electrons.