Chemistry Lecture Review - Atom to Nuclear Chemistry

Flashcards covering key vocabulary from the provided lecture notes on the history and structure of the atom, isotopes, ions, Bohr & Lewis Dot models, the periodic table, and nuclear chemistry.

Dalton’s Atomic Theory

Proposed by John Dalton, stating that all matter is composed of atoms, atoms of the same element are identical, atoms combine in whole-number ratios, and atoms rearrange in chemical reactions.

Cathode Ray Tube

An instrument used by J.J. Thomson, leading to the discovery of the electron.

Electron

A subatomic particle discovered by Thomson, located outside the nucleus, and carrying a negative (-1) charge.

Nucleus

The dense, positively charged central core of an atom, discovered by Rutherford through his gold foil experiment.

Bohr's Atomic Model

Describes electrons as being arranged in specific energy levels or orbits around the nucleus.

Proton

A subatomic particle found in the nucleus with a positive (+1) charge.

Neutron

A subatomic particle found in the nucleus with no electrical charge (0).

Atomic Number

The number of protons in an atom, which determines the element.

Atomic Mass / Mass Number

The total number of protons and neutrons in an atom, which determines the atomic mass.

Mass Number Equation

Mass number = protons + neutrons.

Charge Equation

Charge = protons – electrons.

Isotope

Atoms of the same element that have the same number of protons but different numbers of neutrons, leading to different mass numbers.

Average Atomic Mass Formula

Calculated as the sum of (mass of each isotope × its natural abundance).

Ion

An atom that has a net electrical charge due to the loss or gain of electrons.

Cation

A positively charged ion, formed when an atom loses electrons.

Anion

A negatively charged ion, formed when an atom gains electrons.

Valence Electrons

Electrons located in the outermost shell of an atom.

Determining Valence Electrons

For 'A' groups on the periodic table, the number of valence electrons is equal to the group number.

Groups (Periodic Table)

Vertical columns on the periodic table; elements in the same group have similar chemical properties and the same number of valence electrons.

Periods (Periodic Table)

Horizontal rows on the periodic table; elements in the same period have the same number of electron shells.

Properties of Metals

Typically shiny, malleable, ductile, and good conductors of heat and electricity.

Properties of Nonmetals

Typically dull, brittle, and poor conductors of heat and electricity.

Metalloids

Elements that exhibit properties intermediate between metals and nonmetals (B, Si, Ge, As, Sb, Te, Po).

Alkali Metals

The elements found in Group 1 of the periodic table.

Alkaline Earth Metals

The elements found in Group 2 of the periodic table.

Halogens

The elements found in Group 17 of the periodic table.

Noble Gases

The elements found in Group 18 of the periodic table, known for being inert due to a full valence electron shell.

Transition Metals

The elements found in Groups 3-12 of the periodic table.

Semiconductor

An element that can conduct electricity under certain conditions, such as metalloids.

Nuclear Fusion

A nuclear reaction where two or more atomic nuclei combine to form a single, heavier nucleus, releasing immense energy (e.g., in stars).

Nuclear Fission

A nuclear reaction where the nucleus of a heavy atom splits into two or more smaller nuclei, releasing energy (e.g., in nuclear power plants).

Alpha (α) Radiation

The weakest form of nuclear radiation, represented by the symbol ⁴₂He.

Beta (β) Radiation

A form of nuclear radiation, represented by the symbol ⁰₋₁e.

Gamma (γ) Radiation

The strongest form of nuclear radiation, represented by the symbol ⁰₀γ.

Alpha Decay Effect

In radioactive decay, the nucleus loses 2 protons and its mass number decreases by 4.

Beta Decay Effect

In radioactive decay, the nucleus gains 1 proton (a neutron converts to a proton).

Gamma Decay Effect

In radioactive decay, the nucleus undergoes no change in its number of protons or its mass.