Bonding Flashcards
Define mass number
The total number of protons and neutrons in the nucleus of the atom
Define atomic number
The number of protons in the nucleus of an atom
Define ion
A charged particle formed when an atom loses or gains electrons
Define isotopes
Atoms of an element with the same atomic number but different mass number
Define relative atomic mass
The mass of an atom compared with that of a carbon 12 isotope which has a mass of 12
RAM equation
The sum of (mass of each type of isotope x %isotope)/ The sum of % abundance for all isotopes
Compound definition
Two or more elements chemically combined
John Dalton’s idea of the atom
-All elements made up of small indivisible particles called atoms
-Atoms cannot be created or destroyed
-When they combine they form molecules
Plum pudding model (JJ Thompson)
-Discovered the electron
-Electron is 1/2000 mass of a hydrogen atom
-Atoms are rings of negative electrons embedded in a sphere of positive charge
-Equal number of positive and negative so neutral overall
Rutherford model
-Proved Thompson wrong and said the mass of an atom was mainly due to the protons
-Atoms consist of electrons revolving around a positively charged nucleus
-Positive particles are protons which are X2000 times heavier than electrons
-Nearly all an atoms mass is held in the nucleus
James Chadwick atom idea
-Discovered the neutrons which explained why the nucleus had extra mass
-Equal mass to proton but no charge
-All atoms except hydrogen contain neutrons
Todays atom model
-Central positively charged nucleus composing of protons and neutrons
-Surrounded by electrons orbiting in shells
Relative mass of a proton, neutron and electron
P= 1
N= 1
E= 1/1840
Relative charge of a proton, neutron and electron
P= +1
N= 0
E= -1
Position in the atom of proton, neutron and electron
P= in nucleus
N= in nucleus
E= orbiting nucleus in shells
