Atomic Structure and Isotopes Lecture Notes

This flashcard set covers the fundamentals of atomic structure, including subatomic particles, atomic numbers, mass numbers, isotope definitions, and analytical methods like mass spectrometry.

Protons

Subatomic particles with a positive electrical charge, a mass of $1.672623 \times 10^{-24}\,g$, and a relative mass of $1.007\,u$.

Electrons

Subatomic particles with a negative electrical charge and a relative mass of $0.0005\,u$, located in the space around the nucleus.

Neutrons

Subatomic particles with no electrical charge and a mass of $1.009\,u$.

Law of electrostatic attraction

A law stating that like charges repel and unlike charges attract.

Atomic Number ($Z$)

The number of protons in the nucleus of an atom, which is identical for all atoms of the same element.

Mass Number ($A$)

The total number of protons and neutrons in the nucleus, calculated as $\text{number of protons} + \text{number of neutrons}$.

Atomic mass unit ($u$)

A standard unit of mass defined as exactly $\frac{1}{12}$ the mass of one $C\text{-}12$ atom, equivalent to $1.66054 \times 10^{-24}\,g$.

Isotopes

Atoms of the same element that have the same atomic number ($Z$) but a different number of neutrons, resulting in different mass numbers ($A$).

Nucleons

A collective term for the total number of protons and neutrons in the nucleus.

Protium

An isotope of hydrogen containing $1$ proton and $0$ neutrons.

Deuterium

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

Tritium

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

Mass spectrometer

An instrument used to experimentally determine the masses of isotopes and their relative abundances through vaporization, ionization, acceleration, deflection, and detection.

Mass spectrum

A plot of the relative abundance of charged particles versus the ratio of mass/charge ($m/z$).

Percent Abundance

The ratio of the number of atoms of an individual isotope to the total number of atoms of all isotopes of 그 element, expressed as $\frac{\text{number of atoms of an individual isotope}}{\text{total number of atoms of all isotopes of that element}} \times 100$.

Atomic Weight

The weighted average of the atomic masses of all naturally occurring isotopes of an element, as reported on the periodic table.

Dalton

An alternative name for the atomic mass unit ($u$) or amu.

Nucleus

The central part of the atom where protons and neutrons are located; the atom itself is described as being mostly empty space.