Study-Unit Description

Study-Unit Description


TITLE Physical Chemistry of Liquids and Solutions

LEVEL 03 - Years 2, 3, 4 in Modular Undergraduate Course



DESCRIPTION 1. Liquids: A look at phase diagrams, order in liquids, classification of liquids,intermolecular forces, equations of state.
2. Thermodynamic properties of pure liquids: Thermodynamics of phase equilibria, chemical potential of gases, unary phase diagrams.
3. Liquid crystals: Order in liquid crystals, molecular structure and liquid crystals.
4. Mixtures of non electrolytes: Thermodynamic properties of liquid mixtures, ideal mixtures, partial molar quantities, vapour pressure of liquid mixtures, colligative properties, thermodynamic measures of non ideality, solubility and the supercritical state.
5. Phase diagrams for multicomponent systems: The phase rule, vapour liquid equilibria in binary systems, liquid-solid equilibria in binary systems, ternary systems, partition coefficients.
6. Polar liquids: dielectric properties, water, structural properties of liquid water, non aqueous polar liquids.
7. Solutions of electrolytes: hydration of ions, ionic transport, the ionic atmosphere, ionic association, ionic activities in solution.
8. Chemical equilibria in solution: Equilibrium electrochemistry, solubility of salts, acid and base strengths, equilibria in non aqueous polar solvents.
9. Liquid interfaces: interfacial tension, adsorption at interfaces, surface active agents, adhesion and cohesion, wetting and contact angle, spreading, nucleation processes.
10. Colloidal systems: formation of colloidal dispersions, colloidal stability, aerosols, foams, emulsions.

Study-Unit Aims:

The aims of this study-unit are to provide students with sound knowledge of phase behaviour of single and multicomponent systems; the properties and behaviour electrolyte systems and the properties of interfaces and colloidal systems. Furthermore, students will also be trained to perform physical chemistry experiments involving, phase behaviour, electrochemistry and surfactants as well as interpret results.

Learning Outcomes:

1. Knowledge & Understanding:

By the end of the study-unit the student will be able to:
- Recall the factors that are important in determining the strength of various intermolecular forces;
- Explain phase behaviour through thermodynamics and from molecular perspective;
- Apply thermodynamics in calculations involving phase behaviour;
- Interpret phase diagrams of single and multicomponent systems and use phase information to calculate the amounts of different phases in equilibrium;
- Explain the properties of ideal solutions and ideal dilute solutions from a thermodynamic and molecular perspective;
- Recall Raoult’s Law and Henry's Law and use these laws to perform calculations of vapour pressure of components in non-ionic liquid mixtures;
- Recall the expressions for the distribution coefficient and the partition coefficient and use them to determine the distribution of solute between two solvents;
- Calculate activity coefficients from phase data as well as from the Debye-Huckel Limiting Law;
- Determine the concentration and molar mass of a non-volatile non-electrolyte from its effect on the colligative properties of a solution;
- Explain the difference between the magnitude of changes in colligative properties caused by electrolyte compared to those caused by non-electrolytes;
- Describe the effects of solute concentrations on the vapour pressure, boiling point, freezing point, and osmotic pressure of a solution, and calculate any of these properties given appropriate concentration data;
- Recall the ideal solubility law and use the equation of ideal solubility for calculations relevant to the equation;
- Explain transport properties of ionic transport in solutions electrolyte solutions under the influence of an electric field in terms of ion-ion interactions and ion-solvent interactions;
- Use data involving ionic transport properties such as ionic conductivity and mobility to determine various properties of ions as well as physical constants for electrolytes;
- Explain how an electrochemical cell is made up of two half cells where reduction occurs at the cathode and oxidation at the anode;
- Define the standard reduction potential and use it to determine cell potentials;
- Use cell potentials to determine thermodynamic properties of redox reactions, transport numbers of ions and activity coefficients;
- Use cell potentials and related electrochemical data in the determination of physical constants for electrolytes as well as electrolyte concentrations;
- Explain the phenomenon of surface/interfacial tension in terms of intermolecular forces;
- Describe how contact angle arises and relate this to interfacial tension; how it can lead to capillary rise an how the latter can be used to determine the surface tension of a liquid;
- Explain why surfactants are active at interfaces;
- Discuss the variation of surface tension of water at various surfactant concentration and how data from these data can lead to the determination of surface excess concentration, the critical micelle concentration and the head-group surface area of a surfactant;
- Discuss the factors which influence the critical micelle concentration;
- Describe how bulk physical properties of aqueous surfactant solutions vary with concentration of surfactant;
- Choose which type/class of surfactant would be best to use to form emulsions, as dispersants and good wetting agents;
- Define the Krafft Temperature and Cloud Point of a surfactant;
- Manipulate the wettability of surfaces;
- Discuss the significant forces between colloidal systems, how an approximate value of the pair potential can be calculated;
- Describe the formation of emulsions and the physical properties required for stable emulsions to form.

2. Skills:

By the end of the study-unit the student will be able to:
- Apply physical chemistry knowledge to quantitative and qualitative problems dealing with phase equilibria, solutions, electrochemistry, interfaces and colloids in order to perform calculations and propose solutions to problems;
- Perform physical chemistry experiments safely;
- Check the correctness and reliability of data and results;
- Interpret correctly and verify the results of physical measurements;
- Discuss results of experimental work in relation to established knowledge.

Main Text/s and any supplementary readings:

Atkins' Physical Chemistry by Peter Atkins and Julio de Paula (2014) ISBN 0073221031.

Murrell J.N. and Jenkins A.D., Properties of Liquids and Solutions, (1994) ISBN 10: 047194419X 2nd ed. by Wiley Interscience.

ADDITIONAL NOTES Please note that a pass in the Practical component is obligatory for an overall pass mark to be awarded.

STUDY-UNIT TYPE Lecture, Independent Study, Practicum & Tutorial

Assessment Component/s Assessment Due Resit Availability Weighting
Practical [See Add. Notes] SEM2 No 20%
Examination (2 Hours) SEM2 Yes 80%

LECTURER/S Emmanuel Sinagra

The University makes every effort to ensure that the published Courses Plans, Programmes of Study and Study-Unit information are complete and up-to-date at the time of publication. The University reserves the right to make changes in case errors are detected after publication.
The availability of optional units may be subject to timetabling constraints.
Units not attracting a sufficient number of registrations may be withdrawn without notice.
It should be noted that all the information in the description above applies to study-units available during the academic year 2020/1. It may be subject to change in subsequent years.