3.2 - Alkanes + Haloalkanes

Alkanes + Petroleum

Alkanes + Petroleum

Describe the conditions of Fractional Columns

350^o heat allows corresponding hydrocarbonds (alkanes) to evaporate and condense at the tray (level) with the temperature of its condensing point

• Called a Temperature Gradient

What is Cracking?

The breaking of long chained Hydrocarbons into short chained alkanes + alkenes → easier to combust into fuels

What are the 2 types of Cracking? (explain + conditions)

• Thermal = 1000^o-700^o at 70 atm

• Catalytic = 450^o, moderate pressure with Zeolite catalyst

What are the products of:

• Thermal Cracking

• Catalytic Cracking

• Thermal = Poly(alkenes)

• Catalytic = Aromatic Hydrocarbons

What is Complete + Incomplete combustion?

• Complete= The burning of a compound in excess Oxygen

• Incomplete = The burning of a compound in an absence of Oxygen

What are the products of:

• Complete combustion

• Incomplete combustion

• Complete = Carbon Dioxide + Water

• Incomplete = Carbon Dioxide + Water + Carbon Monoxide + Carbon (soot)

What are 2 specific downsides to Hydrocarbons environmentally?

• Nitrous Oxides formation

• Acid rain

How do Hydrocarbons contribute to Ground-level Ozone?

→ Issue

Unburnt Hydrocarbons react with surrounding Nitrogen gas in the atmosphere producing Nitrous Oxides - NO_x (Smog)
→ which is dense and harmful to inhale

How do Hydrocarbons contribute to Acid rain?

→ Issue

Some Hydrocarbons contain sulfur, when burnt it producing Sulfur dioxide gas which rises in the atmosphere with clouds, dilutes and condenses into acid rain/ dilute sulfuric acid
→ destroying crops/vegitation

What is a Free radical? (+how is it made)

A reactive atom or molecule with an unpaired electron:

• Formed when UV radiation splits a covalent bond giving the atoms/molecules an electron

***FREE RADICAL STEPS ON WALL***

***FREE RADICAL STEPS ON WALL***

What are the 3 Nucleophillic substitution reactions of Haloalkanes?

• Conditions

• Reagents

1. Haloalkane + KOH/NaOH → Alcohol (warm aq base)

2. Ethanolic KCN + Haloalkane → Nitrile (warm KCN)

3. Haloalkane + Ammonia solution → Amine

What is the Elimination reaction of Haloalkane(s)?

Hydroxide (aka base) + Haloalkane → Alkene (ethanolic hydroxide)