Atomic Structure Flashcards
What is filtration
Used to separate an insoluble solid and a liquid
Eg
Sand and water
What is crystallisation
A method of separating a soluble solid and a solvent
Eg
Copper sulphate and water
What is distillation
Used to separate liquids with different boiling points or a solvent from a solute
Eg
Alcohol dissolved in water
Or
Pure water from salty water
What is fractional distillation
Can be used to separate a mixture of several liquids with different boiling points
Eg
Separating fractions from crude oil
What was the plum pudding model and who created it
J.J Thompson
He discovered the electron
He thought that an atom was a ball of positive charge with negative electrons embedded in them
What was the gold foil experiment
They though that in an atom there would be electrons scattered throughout and they thought the path of a positive alpha particle would be straight through the atom however they figured out that there was dense in the middle because some particles went straight through but some deflected
What did Niels Bohr discover
He adapted the nuclear model by suggesting that electrons orbit the nucleus at specific distances
What did james Chadwick discover
The neutron
What is the size of the radius of an atom
0.1 nanometers
What is the size of the radius of the nucleus
1/1009 of the the atom
What are isotopes
Different forms of the same element they have the same number of protons and electrons but a different number of neutrons
Who was Dmitri Mendeleev
In 1869 he devised a table which formed the basics of the modern periodic table
He realised that some elements were yet to be discovered and so he left gaps for them
He did not follow the atomic mass order strictly he swapped things to fit with other groups
His table was correct because many of his predictions about undiscovered elements were proved correct
What ions do metals form
Positive
What ions do non metals form
Negative
Group 0
Noble gassed
Colourless
Interactive
Boiling points increase as you go down the group
The outer shell is full of electrons do the noble gassed do not react easy
Most noble gassed have one atom
What’s it called when you have one atom
Monatomic
Some examples of noble gasses
Helium
Argon
Neon
Group 1
Alkali metals
Have one electron in the outer shell
Lose the other electron easily to form a positive ion
More reactive the further you go down
Examples of alkali metals
Potassium
Sodium
Lithium
Group 7
Halogens
Have 7 electrons in the other shell
Non metals and consist of molecules made up of pairs of atoms
To become ions they must gain an electron
Becomes less reactive as they go down
Ionic bonding
When atoms form chemical bonds by transferring electrons they form ions
Atoms that lose electrons (metals) become positively charged ions
Atoms that gain electrons (non metals) become negatively charged ions
Ionic bonding occur between a metal and a non metal
What is covalent bonding
Occurs between non metals to achieve a full other shell of electrons are shared instead of donated and received
