Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Paddington Academy AS LEVEL CHEMISTRY PAPER 2 PRACTICE PAPER 19 (structured questions only) Answer all questions Max 80 marks Name …………………………………………………………….. Mark ……../80 ……....% Grade ……… Note – this paper only contains structured questions Page 1 Paddington Academy 1. (Total 5 marks) 2. (6) Page 2 Paddington Academy ……………………………………………………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………………………………………………. (4) ……………………………………………………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………………………………………………. ……………………………………………………………………………………………………………………………………………………………. (5) (Total 15 marks) Page 3 Paddington Academy 3. Compound X is shown below. It is a member of a homologous series of hydrocarbons. (a) (i) Deduce the general formula of the homologous series that contains X. ............................................................................................................... (1) (ii) Name a process used to obtain a sample of X from a mixture containing other members of the same homologous series. ............................................................................................................... (1) (b) There are several isomers of X. (i) Give the IUPAC name of the position isomer of X. ............................................................................................................... (1) (ii) Draw the structure of a functional group isomer of X. (1) (c) At high temperatures, one molecule of C15H32 can be converted into two molecules of X and one molecule of another compound. (i) Write an equation for this reaction. ............................................................................................................... (1) (ii) State the name of the process used to obtain a high yield of X from C15H32 Give one reason why this process is used in industry. Name .................................................................................................... Reason ................................................................................................. ............................................................................................................... (2) (iii) State why high temperatures are needed for this process. ............................................................................................................... ............................................................................................................... (1) Page 4 Paddington Academy (d) Compound X can be converted into compound Y. Compound Y is shown below. (i) Write an equation to show the reaction of Y in a limited supply of air to produce a solid and water only. ............................................................................................................... (1) (ii) When a sample of Y, contaminated with CH3SH, is burned completely in air, a toxic gas is formed. Identify this toxic gas and suggest a compound that could be used to remove the toxic gas from the products of combustion. Toxic gas .............................................................................................. Compound used to remove toxic gas .................................................. ............................................................................................................... (2) (iii) Suggest the name of the process that occurs when the toxic gas in part (d)(iv) is removed. ............................................................................................................... (1) (e) Explain why the boiling points of X and Y are similar. ........................................................................................................................ ........................................................................................................................ ........................................................................................................................ ........................................................................................................................ (2) (Total 14 marks) Page 5 Paddington Academy 4. (a) Hexane (C6H14) is a hydrocarbon which is a component of LPG (liquid petroleum gas), used as a fuel for heating. When burning fuels in boilers it is important to ensure complete combustion. (i) Give two reasons why boilers are designed to ensure complete combustion. Reason 1 ............................................................................................ ............................................................................................................. Reason 2 ............................................................................................ ............................................................................................................. (ii) Write an equation for the incomplete combustion of hexane. ............................................................................................................. (iii) Suggest how an engineer or a chemist could demonstrate that the combustion of hexane in a faulty boiler was incomplete. ............................................................................................................. (5) (b) Branched chain alkanes are often preferred as fuels. Draw the structure of two branched chain isomers of hexane and name the first isomer. Isomer 1 Isomer 2 Name of isomer 1 ........................................................................................ (3) (c) Hexane can be cracked in the presence of a catalyst to produce another hydrocarbon, Z, and methane. (i) Draw a possible structure for Z. (ii) Give a suitable catalyst for this reaction. ............................................................................................................. (iii) Suggest why the product Z has more commercial value than hexane. ............................................................................................................. ............................................................................................................. (3) Page 6 Paddington Academy (d) The overall equation for the production of dichloromethane from methane and chlorine is shown below. CH4 + 2Cl2 → CH2Cl2 + 2HCl (i) Calculate the % atom economy for the formation of CH2Cl2 in this reaction. ............................................................................................................. ............................................................................................................. ............................................................................................................. (ii) Give one reason why this atom economy of less than 100% is an important consideration for the commercial success of this process and predict how a chemical company would maximise profits from this process. ............................................................................................................. ............................................................................................................. ............................................................................................................. (3) (Total 14 marks) 5. Page 7 Paddington Academy 6. (Total 8 marks) Page 8 Paddington Academy 7. A ………………………………………………………………………………………………………………………………………………………………… B ………………………………………………………………………………………………………………………………………………………………… D ………………………………………………………………………………………………………………………………………………………………… (3) Name of mechanism:…………………………………………………………………………………………. (4) Page 9 Paddington Academy Name of mechanism:…………………………………………………………………………………………. (5) Name of mechanism:…………………………………………………………………………………………. (3) (Total 15 marks) Page 10 Paddington Academy 8. Page 11 Paddington Academy Page 12