c1 particles Flashcards
Atom
smallest particle of an element. Atoms have a nucleus containing protons and (usually) neutrons, surrounded by electrons.
Atomic number
number of protons in the nucleus of an atom.
Atomic radius
half the diameter of an atom.
Bond
attractive force between two particles.
Bond length
distance between the centres of two atoms that are chemically joined together.
Chemical symbol
letter or letters used by chemists to represent an element, e.g. the symbol for mercury is Hg.
Electron
subatomic particle surrounding the nucleus of an atom. It has a relative charge of -1, and a very small mass.
Element
substance whose atoms have the same atomic number.
Ion
charged particle formed when an atom, or group of atoms, loses or gains electrons.
Isotopes
atoms with the same number of protons and electrons, but different numbers of neutrons, are isotopes of the same element.
Mass number
number of protons and neutrons in a nucleus.
Molecule
particle consisting of two or more non-metal atoms chemically joined together by covalent bonds.
Neutron
subatomic particle found in the nucleus of an atom. It has no charge and a relative mass of 1.
Nucleus
positively charged central part of an atom, made up of protons and neutrons.
Plum-pudding model
outdated model of the atom in which electrons are embedded in a sphere of positive charge.
Protons
subatomic particle found in the nucleus of an atom. It has a relative charge of +1 and a relative mass of 1.
Shell
region of space in an atom that can hold a certain number of electrons.
Subatomic particle
articles from which atoms are made, including protons, neutrons, and electrons.
Chemical change
change that produces new substances.
Chemical reaction
process in which substances react to form different substances.
Electrostatic forces
forces of attraction or repulsion between electrically charged particles.
Matter
anything that has mass.
Model
description, analogy, or equation that helps you to explain the physical world.
Particle
tiny piece of matter, such as an atom, ion, or molecule.
Particle model
scientific idea used to explain the properties of solids, liquids, and gases.
Physical change
change, such as changes in state that does not result in new substances being made.
State
the form that a substance has (solid, liquid, or gas) under given conditions of temperature and pressure.
