7404 2 QP Chemistry AS 12 Oct 21

Figure 1 shows the Maxwell–Boltzmann distribution of molecular energies in a sample of gas. Figure 1 Do not write outside the box 0 1 . 1 0 1 . 2 Label the y-axis on Figure 1. State why the curve starts at the origin. [1[1mark] mark] 0 1 . 3 State what X indicates on Figure 1. X indicates [1 mark] 0 1 . 4 Half of the gas molecules in the sample are removed. The remaining gas molecules are kept at the same temperature. Draw the new distribution of molecular energies for the remaining gas on Figure 1. [2 marks] 5 *03* Turn over ► IB/M/Jun21/7404/2 0 2 Alkenes react with bromine (Br2) 4 Do not write outside the box 0 2 . 1 Name and outline the mechanism for the reaction of cyclohexene with Br2 Name of mechanism Outline of mechanism [5 marks] *04* IB/M/Jun21/7404/2 0 2 . 2 5 Explain why there is an attraction between a C=C double bond and Br2 [3 marks] Do not write outside the box 0 2 . 3 Draw the skeletal formula of the halogenoalkane formed when buta-1,3-diene (CH2=CHCH=CH2) reacts with an excess of Br2