Materials Flashcards
Atomic mass
Number of protons + neutrons
Neutrons = atomic mass - atomic number
Electrons
- charge , no mass, out side shells 2,8,8
Protons
+ charge, mass of 1 , found in nucleus
Ie. If have an atomic number of 6 = a mass of 6
Neutron
No charge, found in nucleus, mass of 1
h20
Hydrogen oxide, water
C02
Carbon dioxide
Nh3
Ammonia
Compound
2 or more elements
Properties of metals
- high density
- strong
- electrical conductors
- thermal conductors
- malleable e.g squish cans
- solid at room temperature
Properties of non metals
- poor conductors of electricity and heat
- dull , don’t shine
- low melting points
- low density
Pure metal (base metals)
Made from one element e.g silver
Metallic bonding e.
Physical not chemical bond
Alloy
Mixture of two elements
E.g instead of steel, stainless steel
- better
- improved
Common alloys
Bronze = good conductor, low friction - wires
Brass = highly workable, durable, low friction Instruments
Coin metal = highly workable - coins
Ores
A rock that contains elements that can be extracted
Common ores
Iron ore - extracted from the hematitive + magnetite
Magnestite - magnesium oxide + carbonate
Demoncritus
Indivisible particles
Thomson
Plumb pudding model
Positively charges spheres with electrons embedded in them
Bohr
Shell model
Same as Rutherford but electrons orbiting in energy levels
Rutherford
Solar system model
Atom is empty space with positively charged nucleus and electrons orbiting the nucleus
Chadwick
Shell model
Electrons orbit nucleus, which is neutral containing protons and neutrons
Properties of acids
- have hydrogen irons h+
- are chorosive ( burns )
- are sour
- conduct electricity
Properties of alkali or bases
- have hydroxide irons Oh- ( poly atomic iron - more than one element) - are caustic - are bitter - conduct electricity
Ph
Ph is a measure of acidity and alkalinity
Neutralisation
Occurs when you mis acid and alkali
7 is neutral
Acid+ base —> salt + water
Atomic number
Top one
Number of protons( equal to electrons if neutral)
