IB Chemistry Topic 1 Definitions
This page contains our IB Chemistry definitions for topic 1. By learning each one of these definitions, you will fully cover the content for IB Chemistry 'Models of Particulate Matter'.
Absolute Zero
The lowest possible temperature, 0 K (-273°C), where kinetic energy and pressure of a gas are zero
abundance
The ratio of an isotope's natural occurrence to the total occurrence of all isotopes
boiling
A liquid absorbing heat to turn into a gas. Boiling can occur randomly from a liquid's surface.
Boyle's Law
The principle stating that the pressure of a gas is inversely proportional to its volume when temperature is constant
Charles's Law
The principle stating that the volume of a gas is directly proportional to its temperature when pressure is constant
chemical reaction
A reaction that forms new substance(s) by breaking bonds in the reactants and forming bonds in the products, causing an energy change in the system but preserving mass and particles
compound
A substance made up of two or more atoms chemically bonded in fixed ratios and have different properties than their components
condensation
A gas losing heat to turn into a liquid
continuous spectrum
A spectrum of electromagnetic radiation that shows all possible wavelengths
convergence
An emission spectrum's feature where lines are closer together at higher wavelengths
deposition
A gas that loses enough heat to instantly turn into a solid
electromagnetic radiation
Form of energy that travels as a wave
electron configuration
An expression describing the filled orbitals
electrostatic attraction
The attraction of opposite charges between the positive nucleus and negative electrons
element
Simplest substance made from atoms that cannot be broken down
emission spectrum
A line spectrum describing the photons an atom emits when electrons drop energy levels and release energy
empirical formula
The simplified ratio at which a compound's components are chemically fixed
evaporation
A liquid absorbing heat to turn into a gas. Evaporation can occur randomly from a liquid's surface. Synonym for boiling and vaporization.
first ionization energy
The energy required to remove one electron from amole of atoms in a gaseous atoms, expressed in kJ/mol
freezing
A liquid losing heat to turn into a solid
Guy-Lussac's Law
The principle stating that the pressure of a gas is directly proportional to its absolute temperature when volume is constant
heterogeneous mixture
A mixture wherein the components are in different states of matter
homogeneous mixture
A mixture wherein the components are the same state of matter
Ions
These are nuclides that have lost or gained electrons, gaining a positive or negative charge
Isotopes
These are nuclides with different numbers of neutrons, and thus different mass numbers
line spectrum
A spectrum of electromagnetic radiation that shows only particular wavelengths
melting
A solid absorbing heat to turn into a liquid
mixture
A substance made up of more than one element or compound not chemically bonded together so that they retain their individual properties
molar mass
The mass of one mole of atoms, expressed as M and measured in g/mol
molecular formula
The actual ratio at which a compound's components are chemically fixed
moles
The number of anything, often referring to the amount of a substance
nuclear charge
The amount of positive charage in the nucleus, proportional to the number of protons
Nucleon
It is a particle in the nucleus
orbital
A region of space where there is a high probability of finding an electron
relative atomic mass
The weighted mean molar mass of all naturally occurring isotopes of an element relative to Carbon-12 and expressed as Ar
relative ionic mass
The weighted mean molar mass of all naturally occurring isotopes of an ion relative to Carbon-12 and expressed as Mr
relative molecular mass
The weighted mean molar mass of a molecule relative to Carbon-12 and expressed as Mr
RTP
Conditions of 25°C (298 K) and 100 kPa pressure
shielding effect
The effect of inner electrons taking nuclear charge away from the valence electrons
solute
A substance used to form a solution by being dissolved by a solvent
solvent
A substance used to form a solution by dissolving a solute
STP
Conditions of 0°C (273 K) and 100 kPa pressure
structural formula
The structure in which a compound's components are chemically fixed
sublimation
A solid that absorbs enough heat to instantly turn into a gas
successive ionization energies
The energy required to remove consecutive electrons from a mole of atoms in a gaseous state, expressed in kJ/mol
the Balmer series
The emission series that result from an electron dropping down to the second energy level, emitting visible light
the Lyman series
The emission series that result from an electron dropping down to the first energy level, emitting ultraviolet light
the molar ratio
The proportion of moles between reactants and products in a chemical reaction
valence electrons
Outermost electrons of an atom
vaporization
A liquid absorbing heat to turn into a gas. Vaporization can occur randomly from a liquid's surface. Synonym for boiling and evaporation.
visible light
the part of the electromagnetic spectrum the human eye can see. contains wavelengths from 400nm to 700nm
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