State what is meant by the term partition coefficient.

1. (a)(i)State what is meant by the term partition coefficient.[1]
2. (a)(ii)Ammonia is soluble in both water and organic solvents. An aqueous solution of ammonia is shaken with the immiscible organic solvent trichloromethane. The mixture is left to reach equilibrium. Samples are taken from each layer and titrated with dilute hydrochloric acid. • A 25.0 cm³ sample from the trichloromethane layer requires 13.0 cm³ of 0.100 mol dm⁻³ HCl to reach the end-point. • A 10.0 cm³ sample from the aqueous layer requires 12.5 cm³ of 0.100 mol dm⁻³ HCl to reach the end-point. Calculate the partition coefficient, Kpartition, of ammonia between trichloromethane and water. Kpartition =[2]
3. (a)(iii)Butylamine, C₄H₉NH₂, is also soluble in both water and organic solvents. Suggest how the value of Kpartition of butylamine between trichloromethane and water would compare to the value of Kpartition calculated in (ii). Explain your answer.[2]
4. (b)(i)Explain why butylamine is basic.[1]
5. (b)(ii)Write an equation to show butylamine reacting as a base.[1]
6. (b)(iii)State how the basicity of butanamide, C₃H₇CONH₂, compares to that of butylamine.[1]
7. (b)(iv)State a reagent for the conversion of butanamide into butylamine.[1]