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• Analytical chemistry deals with the separation, identification, and quantification of matter using classical and modern scientific methods.
• Analytical chemistry characterizes the composition of matter qualitatively and quantitatively, improves analytical methods, extends existing methods to new samples, and develops new methods for measuring chemical phenomena.
• The scope of analytical chemistry involves measuring the chemical composition of materials.

Scope of Analytical Chemistry

• Analytical chemistry determines the composition and quantity of matter present.
• Analytical chemists detect traces of toxic chemicals in water and air.

Qualitative Analysis

• Qualitative Analysis identifies elements, ions, or compounds in a sample and reveals what chemicals are present.
• Qualitative analysis involves the detection of the component that is present.

Quantitative Analysis

• Quantitative analysis determines the amounts of constituents present in a sample.
• Reactions should complete and give clear, known products.
• Quantitative analysis can be divided into volumetric, gravimetric, and instrumental types.

Volumetric Analysis

• Volumetric analysis measures the volume of a solution containing enough reagent to completely react with the analyte, also called titrimetric analysis.

Gravimetric Analysis

• Gravimetric analysis determines the mass of the analyte or a chemically related compound.

Instrumental Analysis

• Instrumental analysis methods measure physical or chemical properties with special instruments and compares those properties to standard methods.
• Spectroscopic methods measure the interaction between electromagnetic radiation and analyte atoms or molecules or the production of radiation by analytes.
• Electroanalytical methods measure electrical properties like pH, electrodeposition, voltammetry, thermal analysis, potential, current, resistance, and electrical charge quantity.
• Separation methods isolate one or more components from solid, liquid, and gas mixtures and involve precipitation, volatilization, ion exchange, extraction with solvent, and various chromatographic methods.

Modern Analytical Chemistry

• Modern analytical chemistry often uses instrumental analysis and focuses on new applications.
• Analytical chemistry discovers new drugs

Quantitative Analysis

• The concentration of O2 and CO2 are daily measured to diagnose and treat illnesses.
• Quantitative measurement of ionized Ca in blood serum helps diagnose parathyroid disease in humans.
• Quantitative N determination in food establishes protein content.
• Quantitative analysis of raw materials and final product in the industrial production lines is also important.
• Measurements of K, Ca, and Na ions in body fluids help physiologists study the role of these ions in nerve-signal conduction, muscle contraction, and relaxation.
• Materials scientists rely on quantitative analyses of crystalline germanium and silicon in semiconductor device studies.

Steps in a chemical analysis

• Define the problem, select analytical procedures, obtain a sample through sampling, prepare the sample for analysis, perform chemical separations if needed, perform the measurement in the analysis, calculate the results, and report.

Expressing Solution Concentration

• Diluted or concentrated solutions qualitatively express the concetration of solutions, with dilute solutions having relatively small amounts of solute and concentrated solutions having large amounts.

Solute concentration

• Concentration denotes the amount of solute in one liter of a solution.
• Percent by mass equals the (mass of solute / mass of solution) x 100.

Calculating Mass Percentage

• Mass percentage (w/w) concentration is expressed as the percent of one component in the solution by mass.
• Mass% of A = A / (A + B) * 100, where A is the solute and B is the solvent.

Volume Percentage

• Volume percentage (V/V) expresses concentration as a percent of one component by volume.
• % V/v = (Volume of solute (mL) / Volume of solution (mL)) x 100

Weight - Volume Percentage

• Weight - Volume Percentage (% w/v) describes the amount of solute present in 100 mL of solution.
• % w/v = (Weight of solute (g) / Volume of solution (mL)) x 100

Parts per Million (ppm).

• Parts per million (ppm) measures the parts of a component per million parts (10^6) of the solution.
• PPM = (Weight of solute (g) / Volume of Solution (ml) )X 10^6

PPM Realtionship

• PPM = M x M.Wt x 1000
• PPM = N x Eq.Wt x 1000
• 1g/m³ = 1mg/L = 1µg/mL

Conversions

• A solution with a concentration of 1.25g/L has a concentration of 1250ppm
• 1. 25g = 1.25 x 1000mg = 1250mg
• A solution with a concentration of 0.5mg/mL has a concentration of 500ppm.
• 1mL ÷ 1000mL/L = 0.001L
• 0. 5mg/0.001L = 500mg/L = 500ppm

Avogadro's Number

• Mole: which is Avogadro's number (6.022×1023) of atoms, molecules, ions or other species.
• In grams, it is the atomic, molecular, or formula weight of a substance.
• 1 mole of substance yields to many particles as there are atoms in 12 g of C-12

Understanding Molar Mass

• Number of moles = mass of sample (g) / molar mass (g/mol)
• Molecular Weight = Sum. Of atomic weight

Molarity

• Molarity (M) expresses moles of solute per liter of solution.
• Molarity = moles of solute / volume of solution in liters

Conversions for molar mass

• Number of moles = Given mass of solute / Gram formula mass of solute
• Litre of solution= mls (cm³) of solution/1000
• Molarity Mass of solute/Gram formula mass of solute= X 1000/(V ml(cm³))
• What is the molarity of an 85.0mL ethanol (C2H5OH) solution containing 1.77g of ethanol?
• mass in grams/Molar mass

Normality

• Normality is the number of equivalents of solute dissolved in one liter of solution, measured in equivalents per liter.
• Normality = No. of equivalents of solute / liter of solution

Normality Equations

• No. of equivalents (n)= Weight (g)/Equivalent Weight (g/eq)
• n = No. of (H) atoms for acids for HCl = 1
• n = No of OH groups for bases for NaOH = 1
• n = No of Cation atoms (M+) for salts for Na2CO3 =2
• n = No. of gained or lost electrons for oxidants and reductants for KMnO4 -7

Molality

• Molality, m, expresses moles of solute dissolved inexactly one kilogram of solvent
• Molality = moles of solute / mass of solvent in kilograms

Solution Terms

• Mole fraction describes the ratio of the number of moles of that component to the total number of moles of all components.
• XA = moles of A / (moles of A + moles of B + moles of C + ....)

Types of solutions

• Homogenous mixture
• Solution: Homogeneous mixture of two or more substance produce from dissolved (disappeared) solute particle (ions, atoms, molecules) (lesser amount) between solvent particle (larger amount).
• Solute (lesser amount) + Solvent (larger amount) → Solution NaCl(s) + H2O(l) → Salt Solutio.
• Dilute and concentrated.
• A concentrated solution: large amount.
• A dilute solution: small amount of solute
• Unsaturated solutions: the amount of solute that is less than the solubility limit.
• A saturated solution : no more solute can dissolve in a solvent at a given temperature, or if it equals the capacity of solvent.
• A super saturated solutions contains of amount of solute that exceeds the normal solubility limit

Preparing Solutions

• Solutions containing a precise mass of solute in a precise volume of solution are called stock (or standard) solutions.
• A volumetric flask should be used.
• Aliquots (carefully measured volumes) of the stock solution can then be diluted .
• (carefully measured volumes) of the stock solution can then be diluted to any desired volume

Dilution Formula

• M stock × V stock = M diluted × V diluted

Volumetric analysis

• Volumetric analysis is a general term for a method of quantitative chemical analysis in which the amount of a substance is determined by the measurement of the volume that the substance occupies.
• Volumetric analysis is commonly called titration

Titration

• Titration determines the unknown concentration of a known reactant.
• A reagent, called the titrant or titrator, of a known concentration, of a known concentration is used to react with a solution of the analyte or titrant, the concentration that is not known
• A primary standard solution is a highly purified compound that serve as a reference material in all volumetric titrimetric methods.

Primary standard solution Important requirements for a primary standard

• High purity and Stability
• Not affected or interact in one way or another
• Modest cost with Reasonable solubility and large molar mass .
• The endpoint is the point at which the titration is complete, according an indicator.
• The equivalence point is the volume of added titrant at which the number of moles of titrant is equal to the number of moles of analyte = 7

Types of titrations

• Neutralization
• Precipitation
• Redox
• Complexometric titrations

Acid-base titrations

• Also known as Neutralization titration : occurs between an acid and a base, when mixed in solution.
• Common indicators, their colours, and the pH range in which they change colour, are given in the table below, when more precise results are required, or when the titration constituents are a weak acid and a weak base, a pH meter or a conductance meter are used.

Precipitation titration

• Precipitation titration: depends on the combination of ions to form a simple precipitate.
• Mohr method: a method depend upon formation a colored precipitate for the determination .

Redox titration

• Redox titration: redox reaction between an oxidizing agent and a reducing agent.

Complexometric titration

• Complexometric titration is the formation of a complex between the analyte and the titrant.
• . The chelating agent Ethylenediaminetetraacetic acid (EDTA) is very commonly used . A common example is Eriochrome Black T and muroxide for the titration of calcium and magnesium ions.
• EDTA is a common titrant

Successful Titrimetric Analysis

• The Titrant standards and reaction.
• A few rules of thumb for designing a successful titration:
• Standard or standardized a Stable and a well-defined

Volume Measurements

• titrant's and sample's are critical or volume or mass
• There must be a definite chemistry, products must have a equilibrium constant
• Should be known rate with a highy purity

Calculate volume analysis

• Known weights of the regents help with stnadard solutions a definite volumes.
• Weight=Mass * volume

Normal solutions

• Normal solution is one that contains 1gm equivalent weight per liter of solution.
• N= Weight eq.wt

1000 Volume(mL)

Molar Equation

• Where M=Weight/(M.Wt) * 100/L

Solution

• A= product +bB

Volume Equations

• MA × VA = MB × VB (R=b/a) volume
• Equivalent weight in neutralization

Acids

• Acid contains of replaceable hydrogen.
• Volume weight.

Base Volume

• Volume is a replaceable hydrol group.
• M.wt base , No. of active OH

Acids-Bases

Arrhenius Theory

• Acid ionizes in water to give hydrogen ion and H3O + HA + H2O → H3O + + A
• Base any substance that ionizes in water to give hydroxyl ions.
• M(OH)n → Mn+ + nOH - -

Bronsted-Lowry Theory

• Bronsted-Lowry: Acid gives a Protion while a base takes Proton

Lewis Theory

• Lewi Acids takes electrons

Acids disolve in waters

• When an acid or base is dissolved in water, it will dissociate, or ionize

Acid Base Equation in waters

HOAC +H2O → H3O++OAc

pure water

• Pure water ionizes slightly, or undergoes autoprotolysis (self-ionization of solvent to give a cation and anion):-

1. Acid Constant

-k=H*O/HO