Post-SLS: Cracking

What are hydrocarbons?

• organic compounds that contain mostly hydrogen and carbon

• organic compounds that contain only hydrogen and carbon

• organic compounds that contain hydrogen, carbon, oxygen and nitrogen

Alkanes are hydrocarbons with a general formula of _________.

• C_nH_2n

• C_nH_2n+1

• C_nH_2n+2

Alkenes are hydrocarbons with a general formula of _________.

• C_nH_2n

• C_nH_2n+1

• C_nH_2n+2

Alkenes are hydrocarbons with at least one C=C bond.

Which two molecules are alkenes?

• 
• 
• 
• 

What is cracking?

• Small hydrocarbon molecules combine to form a large hydrocarbon molecule

• Larger hydrocarbon molecules are broken down into smaller hydrocarbon molecules

• Burning of a fuel in excess oxygen to produce carbon dioxide and water

What are the three correct conditions required for cracking to occur?

• ultra-violet light

• presence of a catalyst e.g. aluminium oxide or silicon dioxide

• pressure of 1 atm

• C₂H₆

• C₃H₆

• C₄H₁₀

• C₁₁H₂₂

• C₁₀H₂₀

• C₁₀H₂₂

• C₁₁H₂₂

• C₁₁H₂₄

• H₂

• C₂H₄

• C₃H₈

• C₆H₁₄

Which three are reasons for performing cracking?

• To satisfy the demands for smaller hydrocarbon molecules

• To reduce carbon dioxide emission

• To obtain hydrogen for the manufacture of fertilisers

• To increase the quantity of hydrocarbons that can be used as petrol