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QUESTION 4 Using the given skeletal formula, answer the questions.   Right-click on the button to open the data booklet in a new tab.      4.1 Give the skeletal formula of a structural isomer. [1] 4.2 Give the skeletal formula of a functional isomer [1]   From the following structures:   Right-click on the button to open the data booklet in a new tab.   Right-click on the button to open the data booklet in a new tab.        4.3 Identify the type of isomer. [1]     [3]

QUESTION 5   Compounds containing different halogen atoms covalently bonded together are called interhalogen compounds.   5.1 One interhalogen compound can be prepared by the reaction between iodine and fluorine. This compound has Mr = 222 and the percentage composition by mass is: F, 42.8; I, 57.2. Calculate the molecular formula of this interhalogen compound. [3] 5.2 Another interhalogen compound has the formula ICl. Draw a ‘dot-and-cross’ diagram of a molecule of this compound, showing outer shell electrons only. Explain whether or not you would expect this molecule to be polar. [2]     [5]  

1.5 Carbon and silicon have the same outer electronic structure. Why is a Si–Si bond weaker than a C–C bond?

1.20 Which stage in the free radical substitution of ethane by chlorine has the lowest activation energy?     Right-click on the button to open the data booklet in a new tab.    

1.22 Chlorofluorocarbons damage the ozone layer by undergoing reactions with a free radical mechanism. The first stage of this is initiation. Which equation is most likely to be the initiation stage when chlorofluoromethane is involved in such a reaction?     Right-click on the button to open the data booklet in a new tab.     

QUESTION 6   When 2.00 mol of PCl5(g) are decomposed at 450 K and 1.00 × 105 Pa the resulting equilibrium mixture contains 0.800 mol of Cl2 (g).   PCl5 (g) < == > PCl3 (g) + Cl2 (g)   6.1 Calculate the partial pressure of phosphorus (V) chloride, pPCl5, in this equilibrium mixture. [2] 6.2 Write the expression for the equilibrium constant, Kp, for the decomposition of PCl5(g). [1]     [3]

1.24 Which organic compound would not give either a yellow precipitate when treated with alkaline aqueous iodine or an orange precipitate when treated with 2,4-dinitrophenylhydrazine reagent?

1.9 Dicarbon monoxide, C2O, is found in dust clouds in space. The structure of this molecule is C=C=O. The molecule contains no unpaired electrons. How many lone pairs of electrons are present in a molecule of C2O?

1.21 Fluorine and iodine are Group 17 elements. Their melting points are different due to differing strengths of the van der Waals’ forces between molecules. Which row is correct?      Right-click on the button to open the data booklet in a new tab.  

QUESTION 3 This question is about an ester with molecular formula C4H8O2   The infra-red spectra of the ester and of another compound, X, are shown. X decolourises bromine water and is not an ester or an acid.   Right-click on the button to open the data booklet in a new tab.     Right-click on the button to open the data booklet in a new tab.       3.1 Draw the displayed diagrams of a possible isomer with the formula C4H8O2 that is an ester. [1] 3.2 Give the reagents and conditions needed to produce an ester. [2] 3.3 Explain the differences between these two spectra, with particular reference to the peaks with wavenumbers above 1500 cm–1. [3]     [6]