Mass Spectrometry and EM Radiation Notes — Vocabulary Flashcards

30 vocabulary flashcards covering key terms from the notes on mass spectrometry and electromagnetic radiation.

Element

A pure substance consisting of only one type of atom; matter is composed of elements.

Pure element

A sample containing only one element.

Atom

The basic unit of an element, with a nucleus of protons and neutrons and electrons orbiting; atoms are mostly empty space.

Nucleus

The center of the atom that contains protons and neutrons; its radius is about 10^-5 of the atom.

Proton

Positively charged subatomic particle in the nucleus; mass about 1 amu.

Neutron

Electrically neutral subatomic particle in the nucleus; mass about 1 amu.

Electron

Negatively charged subatomic particle that orbits the nucleus and has much smaller mass than protons/neutrons.

Atomic Number (Z)

Number of protons in an atom; defines the element’s identity and is a whole number on the periodic table.

Mass Number (A)

Total number of protons and neutrons in an atom; varies among isotopes of the same element.

Isotope

Atoms of the same element with different numbers of neutrons; same Z, different A.

Atomic Mass

Weighted average of the masses of all naturally occurring isotopes of an element; not necessarily the mass of any one atom.

Atomic Mass Unit (amu)

1/12 the mass of a Carbon-12 atom; a unit for atomic masses.

Mole

A group of Avogadro’s Number of particles (NA); NA = 6.022×10^23 mol^-1.

Avogadro’s Number (NA)

6.022×10^23 mol^-1; number of particles per mole.

Molar Mass (M)

Mass of one mole of identical particles; given in g/mol and numerically equal to atomic mass in amu.

Coulomb (C)

The SI unit for electric charge.

Elementary Charge (e)

Magnitude of the charge of a single electron or proton; e = 1.6×10^-19 C; electron = -e, proton = +e.

Charge Number (z)

Charge of a particle in units of e; z is dimensionless; not to be confused with atomic number Z.

Ion

A charged particle formed when electrons are gained or lost.

Mass Spectrometer

Instrument used to determine the relative abundances of isotopes by measuring ions’ mass/charge ratios.

Mass-to-Charge Ratio (m/z)

Ratio of a particle’s mass to its charge; axis in mass spectrometry; z is assumed to be 1 in this course.

Photon

A quantum of electromagnetic radiation; exhibits wave-particle duality; energy E = hν = hc/λ.

Planck’s Constant (h)

6.626 × 10^-34 J·s (or 4.136 × 10^-15 eV·s); appears in E = hν.

Electromagnetic Radiation (EM)

Radiation across a wide spectrum; carried by photons; light is a small part; shows wave-particle duality.

Speed of Light (c)

The speed of EM radiation in vacuum; c = 3.00×10^8 m/s.

Wavelength (λ)

Distance between successive crests; often given in nanometers (nm); 1 nm = 10^-9 m; λν = c.

Frequency (ν)

Oscillations per second; measured in s^-1 (Hz); related to energy by E = hν.

Energy per Photon (E)

Energy carried by a single photon; E = hν = hc/λ; often given in eV.

Percent Abundance

Abundance of isotopes expressed as a percentage; used to calculate atomic mass.

Molar Mass in g/mol equals Atomic Mass in amu

The mass of one mole of atoms (g) is numerically equal to the atomic mass of the atom in amu.

Element

A pure substance consisting of only one type of atom; matter is composed of elements.

Pure element

A sample containing only one element.

Atom

The basic unit of an element, with a nucleus of protons and neutrons and electrons orbiting; atoms are mostly empty space.

Nucleus

The center of the atom that contains protons and neutrons; its radius is about 10^{-5} of the atom.

Proton

Positively charged subatomic particle in the nucleus; mass about 1 amu.

Neutron

Electrically neutral subatomic particle in the nucleus; mass about 1 amu.

Electron

Negatively charged subatomic particle that orbits the nucleus and has much smaller mass than protons/neutrons.

Atomic Number (Z)

Number of protons in an atom; defines the element’s identity and is a whole number on the periodic table.

Mass Number (A)

Total number of protons and neutrons in an atom; varies among isotopes of the same element.

Isotope

Atoms of the same element with different numbers of neutrons; same Z, different A.

Atomic Mass

Weighted average of the masses of all naturally occurring isotopes of an element; not necessarily the mass of any one atom.

Atomic Mass Unit (amu)

1/12 the mass of a Carbon-12 atom; a unit for atomic masses.

Mole

A group of Avogadro’s Number of particles (NA); NA = 6.022\times10^{23} mol^{-1}.

Avogadro’s Number (NA)

6.022\times10^{23} mol^{-1}; number of particles per mole.

Molar Mass (M)

Mass of one mole of identical particles; given in g/mol and numerically equal to atomic mass in amu.

Coulomb (C)

The SI unit for electric charge.

Elementary Charge (e)

Magnitude of the charge of a single electron or proton; e = 1.6\times10^{-19} C; electron = -e, proton = +e.

Charge Number (z)

Charge of a particle in units of e; z is dimensionless; not to be confused with atomic number Z.

Ion

A charged particle formed when electrons are gained or lost.

Mass Spectrometer

Instrument used to determine the relative abundances of isotopes by measuring ions’ mass/charge ratios.

Mass-to-Charge Ratio (m/z)

Ratio of a particle’s mass to its charge; axis in mass spectrometry; z is assumed to be 1 in this course.

Photon

A quantum of electromagnetic radiation; exhibits wave-particle duality; energy E = h$\nu$ = hc/\lambda.

Planck’s Constant (h)

6.626 \times 10^{-34} J$\cdot$s (or 4.136 \times 10^{-15} eV$\cdot$s); appears in E = h$\nu$.

Electromagnetic Radiation (EM)

Radiation across a wide spectrum; carried by photons; light is a small part; shows wave-particle duality.

Speed of Light (c)

The speed of EM radiation in vacuum; c = 3.00\times10^8 m/s.

Wavelength (\lambda)

Distance between successive crests; often given in nanometers (nm); 1 nm = 10^{-9} m; \lambda\nu = c.

Frequency (\nu)

Oscillations per second; measured in s^{-1} (Hz); related to energy by E = h$\nu$.

Energy per Photon (E)

Energy carried by a single photon; E = h$\nu$ = hc/\lambda; often given in eV.

Percent Abundance

Abundance of isotopes expressed as a percentage; used to calculate atomic mass.

Molar Mass in g/mol equals Atomic Mass in amu

The mass of one mole of atoms (g) is numerically equal to the atomic mass of the atom in amu.

Molecule

Two or more atoms held together by chemical bonds.

Compound

A substance composed of two or more different elements chemically bonded together in fixed proportions.

Chemical Bond

The attractive force holding two atoms together.

Ionic Bond

Chemical bond formed by the electrostatic attraction between oppositely charged ions, typically between a metal and a nonmetal.

Covalent Bond

Chemical bond formed by the sharing of electrons between atoms.

Cation

A positively charged ion, formed by losing electrons.

Anion

A negatively charged ion, formed by gaining electrons.

Ground State

The lowest energy state of an atom or particle.

Excited State

Any energy state of an atom or particle higher than the ground state.

Emission Spectrum

The pattern of light emitted by excited atoms, unique to each element.

Absorption Spectrum

The pattern of wavelengths absorbed by atoms when incoming light excites electrons to higher energy levels.

Photoelectric Effect

The emission of electrons when light shines on a material, demonstrating the particle nature of light.

Quantization of Energy

The concept that energy can only exist in discrete, specific amounts (quanta).

Electron Shells

Energy levels around the nucleus where electrons are found.

Valence Electrons

Electrons in the outermost shell of an atom, involved in chemical bonding.

Periodic Table

An organized arrangement of elements based on increasing atomic number and recurring chemical properties.

Group (Periodic Table)

A vertical column in the periodic table, containing elements with similar chemical properties.

Period (Periodic Table)

A horizontal row in the periodic table, representing increasing energy levels for electrons.

Metal

Elements typically found on the left and center of the periodic table, characterized by malleability, ductility, conductivity, and a tendency to lose electrons.

Nonmetal

Elements typically found on the right side of the periodic table, generally poor conductors of heat and electricity, and tend to gain or share electrons.