Paper 2 Fractional Distillation Alkanes Chapter 7 — Organic Chemistry Crude oil is a mixture of many different What is the general formula for an alkane? ______. What is the formula for the 7th Alkane? Fractional Distillation separates the hydrocar- How many double bonds do alkanes contain? Crude Oil bons into groups called ______. Name the first four alkanes. Crude oil is a (renewable/ Each fraction will have hydrocarbon molecules infinite/finite) resource found with a similar number of ______. Complete that table on alkanes in rocks. The fractions are then processed for use by the Name Crude oil is the remains of ______industry. plants and animals buried in mud (hundreds/ Number of Petrol, Diesel Oil, Kerosene, Heavy Fuel Oil and 1 2 3 4 thousands/millions) of years ago. Carbon Atoms Liquefied Petroleum Gases are all produced by fractional distillation of ______and can be Most of the biomass that forms crude oil Number of used as _____. comes from (plankton/trees/biofuel). Hydrogen Atoms Solve the anagrams to get 4 useful materials produced by the petrochemical industry. Crude oil is a mixture of (two/a few/ very 1.) VONTLESS 2.) BLANTURICS 3.) MOLYREPS 4.) GETDENTERS Formula many) compounds. Most of the compounds in crude oil are What changes of state happen to the hydrocarbon molecules as they pass through... a.) ...the heater? b.) ...the fractionating tower? ______which are made from ______Displayed and ______atoms only. Why is kerosene not collected… Structure Most of the compounds in crude oil are a.) ...at a higher point in the fractionating tower? (alkanes/alkenes/alcohols/esters). b.) … at a lower point in the fractionating tower?

Properties of Hydrocarbons Cracking Alkenes

The boiling point, viscosity and flammability of hydrocarbons depends Long Hydrocarbons can be cracked to make ______molecules that are more desirable as ______Alkenes are (more/less) reactive than on the ____ of their ______. or for making useful ______. alkanes Hydrocarbons with larger molecules have ______boiling points (less Name the two main methods for cracking and fill in the conditions for each method ______can be used as a test likely to be _____ at room temperature). for alkenes. Cracking Cracking Hydrocarbons with larger molecules have ______viscosity (they are Label or colour the colour change when ____ runny). Heat until the alkane ______Heat until the alkane ______bromine water reacts with an alkene. Pass them over a ____ catalyst Mix with ______Hydrocarbons with larger molecules have _____ flammability (______to Draw 2 lines to connect the correct set on fire). words When large alkane molecules are cracked they will produce a ______alkane molecules and hy- Alkane Saturated Hydrocarbons are used as fuels because they ______when drocarbon molecules with a double bonds called ______. Alkene Unsaturated burnt. Shorter alkane molecules are in high demand for fuels as they are more ______than longer The difference between alkanes and alkenes is that alkenes have a The complete combustion of hydrocarbons produces ______alkanes and burn with a ______flame. ______. and _____. Balance the following cracking equations. Why is an alkene with 1 carbon atom impossible? Write word and balanced symbol equations for the complete combus- tion of following hydrocarbons. C16H34 —> C12H26 + C2H4 Alkenes can be used to produce ______. Methane + Oxygen —> + . C24H50 —> C15H32 + C3H6 CH + O —> CO + H O Circle the alkenes 4 2 2 2 C19H40 —> C12H26 + C2H4 + C3H6

Propane + —> + .

C3H8 + —> + . Paper 2 Fractional Distillation Alkanes

Chapter 7 — Organic Chemistry Crude oil is a mixture of many different hydro- What is the general formula for an alkane? CnH2n+2 carbons. What is the formula for the 7th Alkane? C7H16 Fractional Distillation separates the hydrocar- How many double bonds do alkanes contain? None Crude Oil bons into groups called fractions. Name the first four alkanes. Methane, ethane, propane and butane. Crude oil is a (renewable/ Each fraction will have hydrocarbon molecules infinite/finite) resource found with a similar number of carbon atoms. Complete that table on alkanes in rocks. The fractions are then processed for use by the Name Methane Ethane Propane Butane Crude oil is the remains of petrochemical industry. plants and animals buried in mud (hundreds/ Number of Petrol, Diesel Oil, Kerosene, Heavy Fuel Oil and 1 2 3 4 thousands/millions) of years ago. Carbon Atoms Liquefied Petroleum Gases are all produced by fractional distillation ofcrude oil and can be used Most of the biomass that forms crude oil Number of as fuels. 4 6 8 10 comes from (plankton/trees/biofuel). Hydrogen Atoms Solve the anagrams to get 4 useful materials produced by the petrochemical industry. Crude oil is a mixture of (two/a few/ very 1.) VONTLESS 2.) BLANTURICS 3.) MOLYREPS 4.) GETDENTERS Formula CH4 C2H6 C3H8 C4H10 many) compounds. solvents lubricants polymers detergents Most of the compounds in crude oil are hydro- What changes of state happen to the hydrocarbon molecules as they pass through... carbons which are made from hydrogen and a.) ...the heater? evaporation b.) ...the fractionating tower? condensation Displayed carbon atoms only. Why is kerosene not collected… Structure Most of the compounds in crude oil are a.) ...at a higher point in the fractionating tower? Would condense before it can rise that high (alkanes/alkenes/alcohols/esters). b.) … at a lower point in the fractionating tower? Too hot for it to condense

Properties of Hydrocarbons Cracking Alkenes

The boiling point, viscosity and flammability of hydrocarbons depends Long Hydrocarbons can be cracked to make smaller molecules that are more desirable as fuels or Alkenes are (more/less) reactive than on the size of their molecules. for making useful polymers. alkanes Hydrocarbons with larger molecules have higher boiling points (less like- Name the two main methods for cracking and fill in the conditions for each method Bromine Water can be used as a test ly to be gases at room temperature). for alkenes. CatalyticCracking Steam Cracking Hydrocarbons with larger molecules have higher viscosity (they are less Label or colour the colour change when runny). Heat until the alkane vaporises Heat until the alkane vaporises bromine water reacts with an alkene. Pass them over a hot catalyst Mix with steam Hydrocarbons with larger molecules have lower flammability (harder to Draw 2 lines to connect the correct set on fire). words Orange Colourless When large alkane molecules are cracked they will produce a shorter alkane molecules and hydro- Alkane Saturated Hydrocarbons are used as fuels because they release energy when carbon molecules with a double bonds called alkenes. Alkene Unsaturated burnt. Shorter alkane molecules are in high demand for fuels as they are more flammable than longer al- The difference between alkanes and alkenes is that alkenes have a The complete combustion of hydrocarbons produces carbon dioxide and kanes and burn with a cleaner flame. double bond. water. Balance the following cracking equations. Why is an alkene with 1 carbon atom impossible? No second carbon Write word and balanced symbol equations for the complete combus- atom to make a double bond. tion of following hydrocarbons. C16H34 —> C12H26 + 2C2H4 Alkenes can be used to produce polymers. Methane + Oxygen —> Carbon Dioxide + Water 2C24H50 —> 3C15H32 + C3H6 Circle the alkenes CH + 2O —> CO + 2H O 4 2 2 2 C19H40 —> C12H26 + 2C2H4 + C3H6 Propane + Oxygen —> Carbon Dioxide + Water

C3H8 + 5O2 —> 3CO2 + 4H2O