Organics Flashcards
(22 cards)
What is crude oil?
A mixture of hydrocarbons, formed from the remains of ancient plankton under high pressure and temperature.
What is fractional distillation?
The separation of crude oil into fractions based on boiling point differences in a fractionating column.
Give two properties of alkanes.
Saturated hydrocarbons (single C–C bonds).
Relatively unreactive (undergo combustion and substitution).
What is the general formula of alkanes?
CₙH₂ₙ₊₂.
Give two properties of alkenes.
Unsaturated hydrocarbons (contain a C=C double bond).
More reactive than alkanes (undergo addition reactions).
What is the general formula of alkenes?
CₙH₂ₙ.
How do you test for unsaturation (alkenes)?
Add bromine water: it decolourises (orange → colourless) if a C=C is present.
What is cracking?
Breaking long-chain hydrocarbons into shorter alkanes and alkenes using heat and a catalyst.
What is a hydrocarbon?
A compound of hydrogen and carbon only
Crude oil is a mixture of ____________?
Hydrocarbons.
What is a polymer?
A large molecule made by joining many small alkene monomers via addition polymerisation.
What is the functional group of alcohols?
-OH (hydroxyl).
What is petrol (gasoline)?
Fraction boiling from 20°C to 70°C. Used as fuel for cars and motorbikes.
What are refinery gases?
Fractions boiling from –10°C to 20°C. Used as LPG for heating/cooking and as feedstock for petrochemicals.
What is kerosene?
Fraction boiling from 120°C to 175°C. Used as jet fuel in aviation and for domestic heating oil.
What is diesel oil?
Fraction boiling from 175°C to 300°C. Used as fuel for diesel engines in trucks, trains, some cars, and generators.
What is fuel oil?
Fraction boiling from 300°C to 350°C. Used as ship fuel, in power‑station boilers, and for industrial heating.
What is bitumen?
The residue boiling above 350°C. Used for road surfacing (asphalt), roofing felt, and waterproofing.
Why is Carbon monoxide poisonous?
restricts oxygen from binding to haemoglobin.
which 2 gases contribute to acid rain?
1) sulfur dioxide
2) nitrous oxides
How does bromine water distinguish between alkanes and alkenes?
Alkanes: No C=C bond → no reaction, solution remains orange.
Alkenes: C=C bond present → undergo electrophilic addition, bromine adds across the double bond → solution decolourises to colourless.
Why are alkenes classified as unsaturated hydrocarbons?
Because they contain a carbon–carbon double bond (C=C), meaning they have fewer hydrogen atoms than the corresponding alkane (maximally saturated) and can add more atoms (e.g., H₂, Br₂) across the double bond in addition reactions—showing they aren’t “fully” saturated with hydrogen.
