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'.
0
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

HL
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. 

HL
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

HL
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

HL
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

HL
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

HL
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

Great Work!

You have now covered all of our topic 1 definitions for IB chemistry.
Now that you have completed these IB chemistry topic 1 definitions, dive into our topic 1 videos for the IB chemistry course.
IB chemistry topic 1 videos

Explored IB Chemistry?

Get stuck into one of our other subjects!
Join 85,000 students, across 130+ countries, in 500+ IB schools. That's half of the IB science graduates worldwide.
Start a 7d free trial