5.10 Concluding remarks -- Chapter 6. Inorganic scale. The salt-like solids -- 6.1 Main factors and issues -- 6.2 Produced water -- 6.3 Scaling minerals -- 6.4 Solubility graphs -- 6.5 Equilibrium and activity -- 6.6 Chemical potential -- 6.7 Solubility of scaling minerals -- 6.8 Sulphate scale -- 6.9 Carbonate scale -- 6.10 Sulphide scale -- 6.11 Amorphous silica -- 6.12 Concluding remarks -- Chapter 7. Naphthenate. The soap-like solids -- 7.1 Acidity of crude oil -- 7.2 Naphthenic acids -- 7.3 Tetracarboxylic acids -- 7.4 Composition of deposits -- 7.5 Deposition parameters -- 7.6 Interface processes -- 7.7 Basic thermodynamics -- 7.8 Size of bubbles and droplets -- 7.9 Field challenges -- 7.10 Concluding remarks -- References -- Appendix A. Temperature in pipelines -- Appendix B. Pipeline wall heat transfer -- Appendix C. Boundary layer temperature profile -- Appendix D. Darcy-Weisbach equation -- Appendix E. Transfer equations -- Appendix F. Friction factor of structured deposits -- Appendix G. Pressure drop in gas pipelines and wells -- Appendix H. Universal velocity profile -- Appendix I. Particle velocity and stopping distance -- Appendix J. Diffusion coefficient -- Appendix K. Deposition-release models -- Appendix L1. Dipole moment of hydrocarbons -- Appendix L2. Regular solution model -- Appendix M1. Viscosity and activation energy -- Appendix M2. Wax-in-kerosene deposition model -- Appendix M3. Pigging model for wax -- Appendix N. Water vapour in natural gas -- Appendix O. Hydrate dissociation pressure -- Appendix P. Boiling point elevation of seawater -- Appendix Q1. Solubility of gases in water -- Appendix Q2. Chemical equilibrium -- Appendix R. Ionic strength and activity coefficient -- Appendix S. Gibbs free energy -- Appendix T. Chemical potential -- Appendix U. Solubility product constants