Analytical Chemistry Lecture 1 2025 PDF

Analytical chemistry (Volumetric, Electrochemical analysis - Chromatographic Separation Techniques) Code: Chm 113 Dr. Wael Mortada  Lecture Introduction and Methods to Express Concentration Dr. Wael Mortada Assistant Professor of Analyt...

Analytical chemistry (Volumetric, Electrochemical analysis - Chromatographic Separation Techniques) Code: Chm 113 Dr. Wael Mortada  Lecture Introduction and Methods to Express Concentration Dr. Wael Mortada Assistant Professor of Analytical Chemistry Contact details: Email: [email protected] WhatsApp: 01022772144 Dr. Wael Mortada  Definition of analytical chemistry. Some applications of analytical chemistry. Classification of quantitative chemical Intended analysis. Learning Definition and classification of Outcomes (ILOs) solution. How to express concentration of solution? Dr. Wael Mortada  What is the analytical chemistry: It is the branch of chemistry that deals with the composition and structure of the matter. In other words, it is the science of determining what matter is and how much of it exists. Some major applications of analytical chemistry are: Assuring the safety and quality of food, pharmaceuticals, and water. Assuring safety of the environmental. Help in diagnosis of some diseases by analysis of biological samples. In forensic medicine. Providing analysis required to trade and commerce Dr. Wael Mortada  Analytical methods Classical Instrumental methods methods Qualitative Quantitative methods methods Dr. Wael Mortada  Qualitative Chemical Analysis ❑ It is a branch of chemistry that deals with the identification of elements or grouping of elements present in a sample. ❑ This analysis does not provide any information about the amount of that chemical component present. ❑ Examples: 1. Iodine Test: It is used to determine whether there is starch present in a sample. 2. Bunsen flame test: The presence of a specific metal or its ions can be determined by using flame test. Dr. Wael Mortada Dr. Wael Mortada Dr. Wael Mortada Quantitative Chemical Analysis It is a branch of analytical chemistry that deals with the determination of the concentration of one or more constituents of a sample. Depending on the property that is used in the determination, quantitative chemical analysis is classified into: Physical methods: They involve the measurement of a physical property that is related to the concentration of the analyte such as density, refractive index, absorption of light, magnetic susceptibility, …… etc. Chemical methods: They depend on a chemical reaction between the analyte and a reagent. The reaction may be neutralization, precipitation, complexometric, oxidation-reduction. Generally, the reaction involves the formation of a new compound. The main classes of quantitative chemical methods are: 1. Volumetric, or titrimetric, analysis. 2. Gravimetric analysis. Dr. Wael Mortada  What is the solution? It is homogenous mixture of two or more components. The solution consists of solute and solvent. The solute is the substance that is being dissolved, it is present in the smaller amount in the solution. The solvent is the dissolving medium, it is present in the larger amount in the solution. Dr. Wael Mortada Dr. Wael Mortada Dr. Wael Mortada Dr. Wael Mortada Dr. Wael Mortada Dr. Wael Mortada Dr. Wael Mortada Dr. Wael Mortada Dr. Wael Mortada Dr. Wael Mortada Dr. Wael Mortada Dr. Wael Mortada  Summary and wrap up - Two types of analytical chemistry (quantitative and qualitative). - There are different ways to express concentration of solution. - ppm and ppb are used for very low (trace) concentrations. - Chemical substances may be electrolytes and non- electrolytes. Dr. Wael Mortada  Evaluation 1. Which of the following is a weak acid? (a) H2SO4 (b) HClO3 (c) HF (d) HCl 2. Which of the following units represent ppm (a) µg/L (b) mg/L (c) g/L (d) Mol/L 3. A sample of sea water contains 28.0 g of NaCl per liter. What is the molarity of sodium chloride in seawater? (Molar mass of NaCl = 58.4 g/mol) (a) 0.479 molar (b) 0.488 molar (c) 0.499 molar (d) 0.510 molar 4. What is the molarity of 5.00 g of NaOH in 750.0 mL of solution? (Molar mass of NaOH = 40.0 g/mol) (a) 0.15 molar (b) 0.167 molar (c) 0.172 molar (d) 0.184 molar Dr. Wael Mortada 5. How many moles of Ca(NO3)2 are there in 75 mL of 0.25 M solution? (a) 0.0188 moles (b) 0.0225 moles (c) 0.0321 moles (d) 0.0451 moles 6. An example of non-electrolyte solution (a) Sugar solution (b) Sea water (c) Hydrochloric acid solution (d) Solium hydroxide solution 7. Ten mg of mercury was found in a 5 L sample of water. What is the concentration of mercury in ppm? (a) 0.2 ppm (b) 2.0 ppm (c) 20 ppm (d) 200 ppm 8. What is the mole fraction of NaOH in an aqueous solution containing 22.8% NaOH by mass? (Molar mass of NaOH = 40 g/mol; H2O = 18 g/mol) (a) 0.57 (b) 0.11 (c) 5.03 (d) 4.28 Dr. Wael Mortada