Chemistry END OF YEAR EXAM Revision Flashcards
John Dalton discovered…
All matter is made of atoms, which are tiny, each element has its own type of atom
John Dalton was wrong when he said…
Atoms are spheres that cannot be broken down, and we cannot create nor destroy them
Mendeleev originally sorted the elements in order of…
Atomic mass
Mendeleev did what to the elements with similar properties?
Put them in the same row
Mendeleev left what for the future?
Gaps in the periodic table
Elements are now arranged in order of…
Atomic number
The columns in the periodic table are…
Groups
The rows in the periodic table are called…
Periods
The group number represents…
The amount of electrons in the outer shell of the atom
Metal Properties
Dense, shiny, malleable, high melting point, good conductors of heat and electricity
Non metal properties
Dull, brittle, low melting point, less dense, poor conductors of heat and electricity
Isotope formula
(% x Amount of neutrons) + (% x Amount of neutrons)
—————————————————————————
100
Filtration separates…
Insoluble solids from a liquid
Separation techniques
Simple distillation, Fractional distillation, filtration, crystallisation, paper chromatography
Paper chromatography separates…
A mixture of liquids using a solvent
Rf value calculation
Distance moved by ink
————————————-
Distance moved by solvent
Two phases of chromatography
Stationary phase, mobile phase
Simple distillation is used to…
Separate a solvent and solute from a solution
Describe simple distillation
The solution is heated until it boils (it should have anti bumping granules in), the solvent vapour evaporates travels up and along to the condenser. When the vapour reaches the cold glass it condenses as a distillate
Fractional Distillation is used to…
Separate mixtures containing more than one liquid with different boiling points
Crystallisation is used to…
Obtain a solute from a solvent
Describe Crystallisation
The solution is heated to evaporate the solvent, leaving the solute that was dissolved into it. The solute is then left and crystals are formed.
In crystallisation the quicker the solvent evaporates…
…the smaller the crystals will be
Element
A single type of atom
Compound
Two or more elements chemically bonded together
Mixture
Two or more elements or compounds not chemically bonded together
Pure
Contains a single type of element or compound
Solvent
A liquid which has something dissolved in it
Solute
A solid that may dissolve
Solution
A mixture of a solute and a solvent
Soluble
A substance that will dissolve
Solid to liquid
Melting
Liquid to solid
Freezing
Liquid to gas
Evaporating/boiling
Gas to liquid
Condensing
Gas to solid
Deposition
Solid to gas
Sublimation
Molecule
Two or more atoms chemically joined together
Solid properties
Fixed volume
Fixed shape
Cannot compress
Liquid Properties
Fixed volume
Takes the shape of the container
Cannot compress
Can flow
Gas properties
Fills a container if sealed
Can be compressed
Can flow
If water is drinkable it is…
Potable
Solid particle arrangement and movement
Closely packed
Uniform pattern
Vibrate on the spot
Liquid particle arrangement and movement
Random pattern
Closely packed
Random movements
Gas particle arrangement and movement
Randomly arranged
Little contact between particles
Fast moving in random directions
Relative mass of a proton
1
Relative mass of a neutron
1
Relative mass of an electron
. 1
——-
1836
Relative charge of a proton
+1
Relative charge of a neutron
0
Relative charge of an electron
-1
Overall charge of the nucleus
+1
Sodium atom electronic configuration
2,8,1
How to make the Rf value more accurate in paper chromatography
Use a longer pice of paper
What to do if there is a that liquid doesn’t dissolve when doing paper chromatography?
Use a different solvent
