History of the atom Flashcards
What is the relative mass of protons, neutrons and electrons
The relative masses of a protons and a neutron are 1, the relative mass of an electron “1/1836”
What is the relative charge of protons, neutrons and electrons
The relative charge of a proton is +1, the relative charge of a neutron is 0 and the relative charge of an electron is -1
Every atom contains equal numbers of … and …
Protons and electrons
What is the atomic number
The number of protons in each atom of an element is known as the atomic number
How are elements in the periodic table arranged in order of
Atomic number (number of protons)
What sub-atomic particles make up the vast majority of the mass of the atom.
Protons and neutrons
What is the mass number
The number of protons plus the neutrons in the nucleus of the atom is called its mass number
How do you work out the number of neutrons
number of neutrons = mass number - atomic number
Nucleus (of an atom)
The very small and dense central part of an atom that contains protons and neutrons.
Proton
A tiny positive particle found inside the nucleus of an atom.
Neutron
A dense particle found in the nucleus of an atom. It is electrically neutral, carrying no charge.
Electron
A tiny particle with a negative charge. Electrons orbit the nucleus of atoms or ions in shells.