Chemistry Flashcards
What is an element
A substance that contains 1 type of atom
What is a compound
A substance which contains 2 or more type of atoms
What is a mixture
A substance which contains 2 or more type of atoms not chemically bonded together
What are the 4 state symbols
Solid, liquid, gas , aqueous
How can you separate an insoluble solid from a solution
Filtration.
How do you separate a salt from a solution
Evaporate the water to produce crystals of salt
How do you separate a liquid from a mixture
Distillation
What are the 3 subatomic particles
Protons , Neutrons, electrons
What are the charges of the subatomic particles
Protons are positive, +1, mass of 1
Neutrons are neutral +0, mass of 1
Electrons are negative -1, mass is very small
What is atomic mass
The number of protons
What is the mass number
Number of protons and neutrons added together
What is an isotope
An element with the same amount of protons but different amount of neutrons
Who thought atoms were hard spheres and elements only had 1 type of atom
Dalton
Who discovered the electron and described atoms like plum puddings
JJ Thompson
Who fired positive alpha particles at gold foil which showed atoms could not be solid
Geiger and marsden
How were elements originally ordered
By atomic weight
Who created the periodic table
Mendeleev
What are group 0
Noble gases
What are group 1
Alkali metals
3 properties of alkali metals
Stored in oil to stop oxidisation
Low density and float in water
Reactivity increases as you go down
What is group 7
Halogens
What is an alloy
Mixtures of metal with an element
Why are metals good conductors
Delocalised ions carry the charge through the metal
When does ionic bonding occur
Metals and non metals
