National 5 Chemistry Exam Revision Nature’s Chemistry

Definitions Define the following terms; Fuel Homologous series Isomer Addition reaction Hydrocarbon Combustion

Definitions Define the following terms; Cracking Saturated Unsaturated

Fuels

When a hydrocarbon is burnt, carbon dioxide and water are produced When a hydrocarbon is burnt, carbon dioxide and water are produced. The following experiment can be used to investigate the products of combustion. Complete the diagram to show the apparatus which would be used to collect the water.

Candle wax is a hydrocarbon Candle wax is a hydrocarbon. Blue cobalt chloride paper and limewater can be used to detect products formed when candle wax is burned. Complete and label the diagram to show the arrangement you would use. Name the product detected using the blue cobalt chloride paper. As the candle burns the funnel becomes coated with soot.Why does this happen?

Homologous Series

Write the general formula for the; Alkanes Alkenes Cycloalkanes Alkanoic acids

Which of the following compounds belongs to the same homologous series as the compound with the molecular formula C3H8?

Name the products formed in this reaction. A very hot flame is produced when ethyne gas (C2H2) burns in a plentiful supply of oxygen. Name the products formed in this reaction. Ethyne is the first member of an homologous series called alkynes. Ethyne has the following structure. All the members of the alkyne series have a triple carbon to carbon bond. Complete the table below. Position in series Name Molecular formula 1st Ethyne C2H2 2nd   C3H4 3rd Butyne

Isomers

Which of the following is an isomer of the compound shown in the red box?

Are these compounds isomers?

Are these compounds isomers?

Are these compounds isomers?

Addition Reactions

Draw the full structural formula for the product formed by the reaction of bromine with each of the following hydrocarbons. a) but-2-ene

Cracking

The diagram shows how paraffin, C12H26 , can be cracked. a) Name the catalyst used in cracking. One of the reactions taking place when paraffin is cracked is b) Identify molecule X.   c) Describe what would be seen when X is added to bromine solution.

Identify X C8H18  C4­H10 + X C6H14  C3H6 + X C12H26  C6H14 + X

Systematic Naming

Name the following; 1. 2. 3. 4.

Name the following: 5. 6. 8. 7.

Name the following: 9. 10. 11. 12.

Drawing full structural formula

Draw the full structural formula for; Hexane Cyclobutane The first member of the alkenes The first member of the cycloalkanes Ethanoic acid Propan-2-ol 2,3-dimethylbutane 2-methylbut-1-ene Pent-1-ene

Draw the full structural formula for: 3-ethyl pentanoic acid 2,2 dimethypentan-1-ol CH2CHCH2CH3 3,3-dimethyl hexanoic acid 3methylbutan-1-ol 2-methylhexan-3-ol CH2CH2 2,4-dimethylpentane

Functional Groups Which functional group is found in the following; Alkenes Alkanols Alkanoic acids Esters

Linalyl ethanoate is made from an alcohol and ethanoic acid Linalyl ethanoate is made from an alcohol and ethanoic acid. To which group of compounds does linalyl ethanoate belong? Identify the hydroxyl group

Methylpropene and an alkane can be use to produce 2,2,4-trimethylpentane, a molecule added to petrol. a) Give the systematic name for the alkane used to produce 2,2,4-trimethylpentane. b) Name the type of chemical reaction shown above.

Complete the word equation for the reaction The dehydration of ethanol to ethane was carried out using the following apparatus. Complete the word equation for the reaction Ethanol  Ethene + ___________________ 2. As a safety precaution, the delivery tube was removed from the water before heating was stopped. Why? 3. Why is the aluminium oxide catalyst described as being heterogeneous?    4. What would the mass of aluminium oxide catalyst be after the reaction was complete?

Esters

Name the ester formed between: Methanoic acid and methanol Propanoic acid and ethanol Ethanol and methanoic acid Propanol and butanoic acid Pentanol and methanoic acid Butanoic acid and methanol

Uses of Carbon Compounds

Uses of Carbon Compounds Why can ethanol be described as a renewable source of energy? State a use of an ester State a use of an alcohol State a use of a carboxylic acid

Energy from Fuels

Calculate Eh from each set of results The temperature of 50 cm3 of water is increased by 12 oC. The temperature of 250 cm3 of water increases from 21.8 oC to 27.9 oC. The temperature of 1000 cm3 of water increases from 8.4 oC to 19.4 oC. The temperature of 1cm3 of water is increased by 20.5 oC.

Calculations based on equations

Calculate the mass of carbon dioxide given off when 1g of methanol is burned. CH3OH + 2O2  CO2 + 2H2O b) Calculate the mass of water produced when 3.2g of ethanol is burned. C2H5OH + 2O2  CO2 + 3H2O

c) Calculate the mass of oxygen required to burn 50g of methane. CH4 + 2O2  CO2 + 2H2O Calculate the mass of water produced when 24g of ethene is burned in oxygen C2H4 + 3O2  2CO2 + 2H2O

Problem Solving

The combustion of alkanals releases heat energy. Make a general statement linking the amount of heat energy released and the number of carbon atoms in the alkanal molecules. Predict the amount of heat energy released, when 1 mole of pentanal burns. PS

The octane numbers for some hydrocarbons are shown. Predict the octane number for hexane. (ii) State a relationship between the structure of the hydrocarbon and their efficiency as fuels. PS

Complete the table b) Care had to be taken when using bromine solution. Give a safety precaution, other than eye protection, which should be taken when completing this PPA. c) Suggest a possible name for hydrocarbon C.

The equation for the reaction is: The diagram below shows how an alkane can be prepared from an alkanoic acid. The equation for the reaction is: Alkanoic acid  alkane + carbon dioxide Complete the table to show which alkanoic acid could be used to produce butane. Alkanoic acid Alkane ethanoic acid methane propanoic acid ethane   butane

Hydroxy acids are compounds that contain both a hydroxyl group and a carboxylic acid group within the same molecule. These compounds are able to form cyclic esters called lactones. Draw the structural formula for the lactone formed when this hydroxyl acid reacts.

Lavender oil is produced from the flowers by steam distillation Lavender oil is produced from the flowers by steam distillation. The flowers are put into a flask with a little water. Steam from a steam generator is blown through them to extract the oil. The mixture of lavender oil and steam distils over. It is condensed and collected. The pieces of apparatus which are used to carry out this steam distillation are shown. show the order in which the pieces of apparatus should be arranged to obtain the mixture.