A thick layer of water stands still over a slab of sodium chloride salt. The salt gradually dissolves and diffuses into water, with the concentration of salt at the slab-water interface kept at 380kgm3. The water is initially pure. The diffusivity of salt in water is 1.2109m2s1. The density of the salt is 2165kgm3. (a) Using the information in TABLE Q2, calculate the salt concentration at 10.2mm from the slab-water interface after 24 hours. (5 marks) (b) Calculate the thickness of the salt dissolved in 24 hours. (6 marks) (c) Calculate the flux of diffusion at the slab-water interface at the 24th hour. ( 5 marks) (d) Draw the diagrams of (i) how the instantaneous diffusion rate changes against time at the slab-water interface. (2 marks) (ii) how the total amount of salt diffused through the slab-water interface changes with time. (2 marks) (e) Calculate the penetration depth at 24th hour and draw the diagram of the concentration profile. (5 marks) Use equations below. =cA4cABcAcA0=erfc(2DADtz)NA=2A(cA4cA4)DANtnAz=0=tDAnA(cA4cA4)2of5MockExamPaperCE3ASPlanuory2023 This examination is subject to the Examination Regulation for Candidates