C1 revision (Chemistry unit 1)

CHEMISTRY 1NANCY

ATOMIC STRUCTURE

Atomic Structure

•Every atom contains:

•Electrons =

•+1 Proton

•No charge Neutron

•-1 Electron

IONIC BONDING

•METALLIC + NON METALLIC = IONIC BOND

•Metal atoms lose electrons to make POSITIVE Ions

•Atoms of Non-metals GAIN electrons to form NEGATIVE Ions

•OPPOSITE CHARGES ATTRACT

COVALENT BONDS

•NON METALLIC + NON METALLIC = COVALENT BONDING

•BY SHARING ELECTRONS

•Simple molecular compound =OXYGEN & DIAMOND

•CHLORINE & CO2 = MOLECULE

SODIUM CHLORIDE IONIC BONDS

•Sodium Metal SUPER REACTIVE

•Chloride gas MAKES YOU SICK

•Through IONIC BONDING they become SODIUM CHLORIDE

LIMESTONE

LIMESTONE AND BUILDING MATERIAL•USED FOR :

•Building STATUES

•Limestone + Clay = CEMENT

•Limestone + Clay +Sand = MORTAR

•Limestone + Clay + Sand + Aggregate [Small stones] = CONCRETE

QUARRYING

•BAD : Noise ; Dust ; Pollution ; Spoilt landscape

•GOOD : Valuable Material ; Employment

LIMESTONE CYCLE

•Calcium Carbonate[CaCo3] THERMAL DECOMPOSITION

• Calcium Oxide [CaO]---> Solid Calcium Hydroxide [Ca(OH)2] --> Calcium Hydroxide Solution [Ca(OH)2 (aq)]

CARBONATES THAT THERMALLY

DECOMP•Calcium Carbonate --> CaO+CO2

•Copper Carbonate --> Copper Oxide + CO2

•Zinc Carbonate --> Zinc Oxide + CO2

•Magnesium Carbonate --> Magnesium oxide + CO2

DECOMPOSING CARBONATES

•Carbonates at the TOP of GROUP 1 are DIFFICULT to DECOMPOSE

EXTRACTING METALS

HOW TO GET METALS

•METAL ORE contains A LOT OF METAL --> Chemically combined with O2 --> have impurities

•1.CONCENTRATE ORE - remove impurities

•2. CHEMICAL REACTIONS - Remove Oxygen --> METAL YAY

PRICES OF METAL AND EXTRACTION•NOT WORTHWHILE to spend a

LOT of money on a process with a CHEAP PRODUCT

•Price changes IF:

•CHEAPER extraction method/ extracts MORE

•Metal INCREASES in VALUE

EXTRACTING SOME OTHER METALS

•Based on REACTIVITY SERIES

•IRON ORE/OXIDE + CARBON --> IRON + CO2

•Anything BELOW Carbon can be oxidised with Carbon

•Creates CO2 as well due to oxygen

EXTRACTING SOME OTHER METALS

•ABOVE CARBON --> MELT & Use ELECTROLYSIS to separate METAL from OXYGEN

•Process&Metal are EXPENSIVE as a lot of ENERGY is used

EXTRACTING SOME OTHER METALS

•COPPER OXIDE + CARBON --> IMPURE COPPER + CO2

•IMPURE COPPER --> ELECTROLYSIS --> PURE COPPER

•Copper ores RUNNING OUT

CRUDE OIL

WHERE IT COMES FROM

•ALWAYS found buried DEEP in ROCK

•e.g. Underwater --> Pipeline carries it up to OIL RIG and to a TANKER

•CRUDE OIL - MIXTURE of compounds ; EASILY separated

HOW TO SEPARATE CRUDE OIL MIXTURE•IDEA :

•Boiling tube has 3 LIQUID COMPOUNDS

•EACH has it’s own BOILING POINT e.g. 70º 150º and 350º [ Temp liquid>Gas]

•Boil to evaporate liquids until ONE IS LEFT

DISTILLATION [separating liquids]

•LOW Boiling point :

• HIGHLY FLAMMABLE

• Good for FUEL

•LOW viscosity [ THICKNESS ]

DISTILLATION [separating liquids]

•HIGH Boiling point :

• LOW FLAMMABILITY

•HIGH viscosity [ THICKNESS ]

CRUDE OIL

•Each product is a HYDROCARBON MOLECULE

FRACTIONAL DISTILLATION

•Crude Oil comes from LEFT-

•HOTTEST TEMP

• Substances EVAPORATE

•Evaporate at different points

•MOLECULE SIZE LARGEST at BOTTOM

CRACKING HYDROCARBONS

•SHORT CHAIN HYDROCARBONS --> TOP of fractional distillation

•HIGH flammability ; LOW viscosity ; LOW boiling point

•VERY USEFUL

CRACKING HYDROCARBONS

•CUT hydrocarbons into smaller pieces to make them MORE USEFUL

•THERMAL DECOMPOSITION

HEATPROOF WOOL

soaked in HYDROCARBON

LIQUID

Pieces of CERAMICCATALYST

HEATHEATED andEVAPORATE

S

CRACKING HYDROCARBONS

•ALKANE becomes [NO double bonds]

•-->

•Shorter Hydrocarbon Chain ; MORE USEFUL because SHORT CHAIN [Has ALL good features]

POLYMERS

POLYMERS•ETHENE is an ALKENE =

FLAMMABLE

•LONG Chain of Ethene - React it and it makes a POLYMER [polymerisation]

•Products of Ethene GAS is different to POLYETHENE [plastic product]

•Molecules called MONOMERS

POLYMERISATIO

•ETHENE --> C2H4

•Double bonds are BROKEN and joins the next ethene molecule

•Substance = Polyethene

•Same process with PROPENE --> POLYPROPENE

BIODEGRADABLE POLYMERS

•In LANDFILL SITES after a few years, POLYMERS will not rot --> VERY UNREACTIVE

•To make them BIODEGRADABLE [Can be EATEN by BACTERIA] you add CORNSTARCH.

NEW POLYMER USES

•PACKAGING food

•Fabric COATING

•HYDROGELS - Absorb a LOT of water

•BREATHABLE fabric - GORTEX

•SHAPE MEMORY polymers - Glasses ; Car Bumpers --> Heat for original shape

ETHANOL

•Make:

•DRINKS

•DISINFECTANT

•PERFUME

•FUEL

FERMENTING

•USE: Sugar ; YEAST ; Water

•Sugar (GLUCOSE) --> ETHANOL + CO2

REACT ETHENE WITH STEAM

•HYDRATION REACTION

•Ethene + Water [steam] --> ETHANOL

COMPARE• FERMENT?

•YES: Cheap

• LOW Temp

•NO:

• CO2

• uses CROP LAND

• ETHENE & STEAM?

•YES: No CO2

•Quick

• LESS People needed

•NO: Expensive

•Non-renewable

EMULSIONS

OIL&WATER

•COMBINES water&Oil

•HOW?

•Emulsifiers keep oil as TINY DROPLETS that spread : NO SEPARATION

EMULSIONS ARE...

•...MORE VISCOUS

•BETTER at COATING [sticky]

•Better TEXTURE

•e.g. Salad DRESSING ; Mayonnaise ; Ice cream ; Milk ; Paint ; Cosmetics

HOW EMULSIFIERS WORK

•e.g. EGG YOLK

•HYDROPHOBIC tail attracts towards OIL

•HYDROPHILIC head REPELS water

•This keeps the oil droplets as DROPLETS

SATURATED AND UNSATURATED

SATURATED AND UNSATURATED

FATS•SATURATED FATS

•SOLID [High MELTING point]

•Come from ANIMALS [butter]

• LESS healthy [+ BLOOD CHOLESTEROL]

•UNSATURATED FATS [ oil ]

• LIQUID [Low MP]

•PLANTS [Olive Oil]

•MORE healthy

• LOWER blood cholesterol

SATURATED AND UNSATURATED

FATS•SATURATED FATS

•NO DOUBLE BONDS

•UNSATURATED FATS [ oil ]

•ONE or MORE DOUBLE BOND

TEST FOR SATURATED FAT

•React substance with UNSATURATED FAT bromine water is COLOURLESS

•SATURATED - NO colour change

WHICH FORM IS BETTER?

•PLANT OIL has LONG hydrocarbon chains - LIQUID

•in SOLID form it’s more useful - SPREADABLE

EARTH AND THE ATMOSPHERE

EARTH STRUCTURE