Accueil Mecanique Electricité Optique Chimie Matière

 

 

Animations Flash ®  pour apprendre la CHIMIE

 

 

 

Généralités

 

01. Réaction simple | combustion du carbone    en  es   

 

02. Identification des ions    en  es

 

Structure des molécules

 

03. Classification périodique des éléments - Lewis    en  es    

 

04. Molécules en 3D   en  es   

 

05. Classification des éléments - Règle duet et octet    en  es   

 

06. Classification - Isotopes - Masse molaire atomique   en  es 

 

07. La mole - masse molaire    en  es   

 

La réaction chimique

 

08. Fer et acide chlorhydrique    en  es

 

09. Transformations spontanées : la pile Daniell   en  es

 

10. Transformations forcées : une électrolyse    en  es 

 

11. Estérification/Hydrolyse | élimination d'un produit  en  es

 

12. Estérification/Hydrolyse | excès d'un réactif   en  es  

 

13. Ajuster les équations rédox    en  es 

 

 

 

 

 

 

 

 

 

 

 

 

 

Cinétique Chimique

 

14. Un facteur cinétique : la température   en  es  

 

15. Un facteur cinétique : la concentration    en  es 

 

Exercices corrigés

 

16. Atomes et molécules | exercice 1    en  es  

 

17. Atomes et molécules | exercice 2    en  es  

 

18. Atomes et molécules | exercice 3    en  es  

 

19. Équilibrer des équations bilans | niveau 0    en  es  

 

20. Équilibrer des équations bilans | niveau 1    en  es  

 

21. Équilibrer des équations bilans | niveau 2    en  es 

 

22. Équilibrer des équations bilans | niveau 3    en  es 

 

23. Réaction chimique en es

 

 

 

 

 

 

 

 

 

 

 

PCCL © 2017

 

 

 

 

 

 

 

 

 

content

 

From air to molecule

 

Air composition

 

Dioxygen, forming air with nitrous.

 

The oxygen necessary for life.

 

 

Volume and mass of air.

 

Character of a compressible gas.

Mass of a given volume of gas.

 

 

A molecular description to understand

 

A first particle model to interpret the compressibility of a gas.

Distinction between mixed and pure body for air and water vapor.

The existence of the molecule.

The three states of water through the molecular description:
- A gas is dispersed and disorganized;
- The liquid state is compact and disordered;
- Solid state is compact, crystalline solids are ordered.

Interpretation of mass conservation during state changes and in mixtures.

 

 

Combustions

 

Combustion requires the presence of reactants (fuel and oxidizer) that are consumed during the combustion of new products are formed.

Combustion of carbon.

Test of carbon dioxide: carbon dioxide reacts with lime water to give a precipitate of calcium carbonate.

Combustion of butane and / or methane.

Tests of carbon dioxide and water formed.

 

The atoms to understand the chemical transformation

 

Atomic interpretation of two or three combustions.

The molecules consist of atoms.

The loss of some or all of the reagents and the formation of products is a rearrangement of atoms into new molecules.

The atoms are represented by symbols, the molecules by formulas.


The equation of the reaction explain the meaning of the transformation (the arrow goes from reactants to products).

The atoms in the products are similar and the same number as in the reactants.

The total mass is conserved during a chemical transformation. Balancing an equation balance.
 

 

Metals, electrons and ions

- Metals daily

Some base metal : iron, zinc, aluminum, copper, silver and gold.

 

- Conduction and electrical structure of matter

 

The electron: understanding the electrical conduction in metals

All metals conduct electricity. All solids do not conduct electrical current. Electrical conduction in metals is interpreted by moving electrons.
 

 

The ion: Understanding the electrical conduction in aqueous solutions

All aqueous solutions do not conduct electrical current.
Conduction of electrical current is interpreted by a displacement of ions.
Constituents of the atom: nucleus and electrons.
Atoms and molecules are electrically neutral, the electron and the ions are electrically charged.
 

 

- Some tests for recognition of ions

 

The forms of Na+, Cl-, Cu2 +, Fe2+ and Fe3 +.
Areas of acidity and alkalinity in aqueous solution.
A neutral aqueous solution contains as many hydrogen ions H+ than OH- hydroxide ions.
In an acid solution, there are more hydrogen H
+ ions than  HO-hydroxide ions.
The dangers of concentrated acid or alkaline products.
 

 

- Reaction between iron and hydrochloric acid interpretation

 

- Hydrogen and chloride ions are present in a solution of hydrochloric acid.
- Criteria for recognition of a chemical change: the disappearance of reactants and appearance of products.
 

 

- Battery (lectrochemical cell) and chemical energy

 

- The chemical species present in a cell containing the chemical energy of which is transferred in other forms of energy when operating.

- The energy involved in a pile from a chemical reaction: the consumption of reagents results in "wear" the battery.
 

 

- Summary of chemical species

 

Is it possible to synthesize the aroma of banana?
The synthesis of chemical species existing in nature can reduce the cost and / or availability. (Isoamyl acetate)

Can we create new chemical species?
The synthesis of chemical species do not exist in nature can improve living conditions. (Nylon or soap)
The nylon and plastics are made of macromolecules.

 

"Chemical or natural ?"

 

- Chemistry of the world, highlighting the ubiquity of chemical species

 

Inventory and classification of some chemical species
Chemical species and natural synthetic chemical species

 

 The world of chemistry: experimental approaches and history of the extraction, separation and identification of chemical species
 

 

Techniques for extracting organic chemical species

 

a) Historical approach
b) The principle of solvent extraction
c) Extraction of chemical species from a 'product' of nature: solvent extraction or steam
 

 

Separation and identification of chemical species

 

Characterization and identification by comparison of a chemical species extracted.
a) chromatography
Principle of chromatography: stationary phase, mobile phase, revelation, interpretation, application to the separation of a mixture of species and analysis.
b) Physical
Tf, bp, density, refractive index, "color", solubilities.

 

- The world of chemistry: the synthesis of chemical species in the laboratory and in industry

The need to synthetic chemistry.

Some examples of synthesis in the heavy chemicals and fine chemicals (high value) from the raw materials of nature and the needs of consumers.

Synthesis of a chemical species

Characterization of a synthetic chemical species and comparison with a natural extract with the same chemical that the species synthesized.

 

Constitution of the matter

 

- Simple models for description of the atom

 

A model of the atom

Nucleus (protons and neutrons), electrons:
Number of charge and atomic number Z.
Number of nucleons A.
Elementary charge, charges of the constituents of the atom.
Electroneutrality of the atom
Mass: mass of the constituents of the atom mass approximation of an atom and its nucleus, considered as the sum of the masses of its constituents.
Size: magnitude of the ratio of the respective dimensions of the atom and its nucleus.
 

 

The chemical element

Definitions of isotopes.
Definitions of the monatomic ions
Characterization of the element's atomic number and symbol.
Conservation of the element in the chemical transformations.

 

A model of the electron cloud

Distribution of electrons in different layers, called K, L, M.
Distribution of electrons for the elements of Z between 1 and 18.

 

- From the atom to the chemical structures

 

The rules of the "duet" and the byte

a) Statement of rules of the stability of noble gas atoms (or "scarce"), chemical inertness.
b) Application to mono-atomic ions stable.
c) Application to molecules with the Lewis model of the covalent bond.
Lewis representation of a few molecules.
Enumeration of pairs of electrons binders and non binders.
Concept of isomerism.

 

The geometry of some simple molecules.

Provision of pairs of electrons according to their number.
Application to molecules having only single bonds.
Representation of Cram.

 

- The Periodic Table
 

 

Periodic table.

Mendeleev's approach to establish its classification; his genius, his mistakes.
The current criteria of classification: Z and the electrons of the outer layer.

 

Using the periodic table.

Chemical families.

Usual formulas of molecules and charges of monoatomic ions; generalization to higher Z elements.
 

 

- Transformations of matter

 

- Tools description of a system

The microscopic scale to macroscopic scale: the mole
Unit amount of substance: the mole.

Avogadro constant, NA
Molar mass "atomic" : M (g mol-1).
Molecular weight molecules.
Molar volume Vm (L.mol-1) to T and P.

Molar concentration of molecular species in solution.

Notions of solvent, solute, solution and aqueous solution.
Dissolution of a molecular species.
Molar concentration of species dissolved in solution unsaturated.
Dilution of a solution.

 

- Transformation of a chemical

 

Modeling the transformation: chemical reaction

Examples of chemical changes.
Initial state and final state of a system.
Chemical reaction.
Writing symbolic of the reaction
Chemical equation.
Reactants and products.
Adjustment of stoichiometric numbers.

 

Matter balance

Introduction to progress.
Expression of the quantities of matter (in mol) of reactants and products during the transformation.
Limiting reagent and maximum progress
Material balance.
This increase in content is accompanied by the construction of a table describing the evolution of the system during processing.

 

- The measurement in chemistry

 

- WHY MEASURE QUANTITY OF MATTER ?

 

From examples taken from everyday life, show the need for different measurement techniques and raise awareness of the choice of a technique based on a target.
 

 

- PHYSICAL RELATED MATTER QUANTITIES

 

Mass, volume, pressure

 

Physical quantities related to the quantities of solid or liquid (mass, volume) and gas (mass, volume, pressure).

Molar volume of an ideal gas pressure and temperature known.

 

- Concentration ; electrolyte solutions

 

Ionic solid.
Obtaining an electrolyte solution by dissolving ionic solids, liquids or gases in water.
Dipolar character of a molecule (permanent dipole): examples of the molecule of hydrogen chloride and water molecule, correlated with the periodic table.
Solvation of ions, interaction between dissolved ions and water molecules. Special case of the proton.
Molar concentration of solute introduced, denoted c, and effective molar concentration of dissolved species, denoted [X].
 

 

- Applications to monitoring of chemical transformation

 

Evolution of a system during a chemical transformation: progress, descriptive overview of the evolution and mass balance.
 

 

- HOW TO DETERMINE THE QUANTITY OF MATTER IN SOLUTION USING A PHYSICAL MEASUREMENT? THE EXAMPLE OF CONDUCTIVITY

 

Conductance of an ionic solution, G

 

Method of measuring the conductance.
Influencing variables (temperature and surface electrodes, surface electrodes, distance between them, nature and concentration of the solution).
Calibration curve G = f (c).

 

Ionic conductivity of a solution, σ

 

Definition from the relationship
G = σ.S / L
Relationship between σ and c.

 

Ionic molar conductivity, li, and the relationship between ionic conductivity and molar conductivity of a solution

 

Using a molar ionic conductivities table of the most common ions.
Comparison of ionic conductivities of the molecular ion H+(aq) and HO-(aq) with other ions.
Limitations of the method of calibration.

 

- HOW TO DETERMINE THE QUANTITY OF MATTER IN SOLUTION BY MEANS OF CHEMICAL REACTION ?

 

Acid-base reactions

 

Examples of acid-base reactions as reactions involving the transfer of protons.
From the writing of each of the reactions, bring out the definition of an acid and a basic sense of

 BrØnsted.

Some common acids and bases.
Acid / base pair.
Pairs of water :

H3O+/H2O ; H2O/HO-(aq).

Water is an ampholyte.

 

Redox reactions

 

Examples of redox reactions such as reactions involving electron transfer.
From the writing of each of the reactions, the emergence, in simple cases, the definition of an oxidizer and a reducing agent.
Couple oxidative / reductive.
Highlighting the need for a method and a formalism to write the equation of a redox reaction.
Using the periodic table to give examples of reducing agents (metals) and among non-oxidizing metals (dihalogen and oxygen).
 

 

Assays direct

 

The chemical reaction as a tool for determining the quantities of matter.
Using a table describing the evolution of the system during the assay.
Equivalence in a dosage.

 

 

 

The creative chemistry

 

 

- ORGANIC CHEMISTRY: From birth to its omnipresence in THE DAILY

 

What is organic chemistry ?

 

Identify the field of organic chemistry.
Natural resources: photosynthesis, biochemical synthesis and hydrocarbon fuels.

 

Carbon building block in organic chemistry

 

How the carbon atom it establishes links with other atoms ?

 

Key dates in the history of organic chemistry

 

The ubiquity of organic chemistry

 

 

- LEARNING TO READ A CHEMICAL FORMULA

 

Introduction

 

An organic molecule has a carbon skeleton, and possibly characteristics of the groups.

 

The carbon skeleton

 

The variety of carbon chains
- Linear chain, branched or cyclic saturated and unsaturated.
Empirical formula, formula developed semi flat topological approach to writing, constitutional isomers demonstrated on some simple examples of the Z isomer and E
- Influence of the carbon chain on the physical properties: boiling point, density, solubility (the examples are taken from the saturated chains).
- Application to fractional distillation.

The modification of the carbon skeleton.
Lengthening, shortening, branching, cyclization, dehydrogenation, or from some industrial applications, oil chemistry, polyaddition of alkenes and ethylene derivatives.
 

 

The group features: introduction to the reactivity

 

a) Recognize the families of compounds: amino, halogenated compound, alcohol, aldehyde, ketone, carboxylic acid.

b) To illustrate the reactivity of alcohols: oxidation, dehydration (elimination), transition to halogenated compounds (substitution).

c) Passage of a group characteristic to another: some examples in the laboratory and in industry
 

 

- The energy in everyday life : The cohesion of matter and energy aspects of its transformations

 

 

Cohesion of the matter

 

The molecule: of atoms, binding energy of a bond AB, rated DAB.

 

Assemblies of molecules: the solid and liquid compared to gas (magnitude of the distances between molecules, in order to disorder), cohesive energy.
 

 

Transformations of matter and energy aspects associated thermal effects

 

Chemical transformations.
Change of state.
Use bond energies to estimate the magnitude of the energy transferred during a reaction involving the chemical species in the gaseous state.
 

 

Some everyday applications of thermal effects

 

Transport and heating : challenges and environmental consequences.

 

Introduction: The issues facing the chemical

 

- Identify the activities of the chemist and the issues of chemistry in society.
- Remove some questions that arise in his professional chemist.

 

- The transformation of a chemical system is it still fast?

 

Slow and fast changes

- Identification of experimental changes fast and slow.
- Identification of experimental kinetic factors: temperature and concentration of reactants.
- Reminders on couples oxidizing / reducing and writing equations of redox reactions.

 

Time tracking of a transformation

- Plotting of curves of change of amount of substance or concentration of a species and the progress of the reaction over time: using the table describing the evolution of the chemical system, operating experiences.
- Speed of response:
Setting the volume rate of reaction expressed in units of quantity of material per unit time and volume.

v = (1/V) x (dx/dt )  where x is the progress of the reaction and V the volume of the solution.
Changes in the rate of reaction over time.
- Half-reaction noted t1/2 :
Definition and determination methods.
Choosing a method for monitoring the transformation depending on the value of t1/2.
A new analysis technique, spectrophotometry: absorbance A quantity measured by the spectrophotometer.
Relationship between absorbance and concentration of a species effective color solution for a given wavelength and for a given thickness of crossing solution.
Monitoring the kinetics of chemical transformation by spectrophotometry.

 

What interpretation given to the microscopic level?

Interpretation of the chemical reaction under shock e effective.
Interpretation of the influence of the concentration of reactive species and temperature on the number of shocks and shock efficient per unit of time.
 

 

- The transformation of a chemical system is it always full ?

 

Chemical transformation is not always complete and the reaction takes place in both directions

- Introduction of pH and its measurement.
- Identification of an experimental chemical transformation given a final progress different from the maximum progress.
- Symbolism write the equation of the reaction: the equal sign =.
- State of equilibrium of a chemical system.
- Rate final progress of a reaction :

 τ = χfinal/ χmaximal.

- Interpretation at the microscopic level of steady state in terms of kinetic impact effective between reactive species on the one hand and the other entities produced.

 

State of equilibrium of a system

- Reaction Quotient, Qr : literal expression based on molar concentrations of dissolved species in a given state of the system.
- Generalization to various examples in aqueous solution homogeneous or heterogeneous (presence of solids).
- Determining the value of the quotient of reaction in the equilibrium state of the system, denoted Qr,éq.

- Equilibrium constant K associated with the equation of a reaction at a given temperature.
-Influence of the initial state of a system on the final stage of completion of a reaction.

 

Changes associated with acid-base reactions in aqueous solution

- Autoprotolysis of the water equilibrium constant called the ionic product of water, denoted by Ke et pKe.

- Scale pH solution acidic, basic and neutral.
- Acidity constant, denoted KA et pKA.

- Comparison of the behavior in solution, at the same concentration, acids and bases them together.
- Equilibrium constant associated with acid-base reaction.
- Diagrams prevalence and distribution of acidic and basic species in solution.
- Zone of turn of a colored indicator acid-base.
- PH-metric titration of an acid or base in water to determine the amount paid to the equity method and to choose a color indicator for an acid-base titration.
- What is the total transformation?
Determination of final progress of a reaction on an example of acid-base titration.

 

- meaning "spontaneous" evolution of a system is predictable ?
The direction of evolution of a chemical system can be reversed ?

 

A self-limiting chemical steady state

- Reaction Quotient, Qr: literal expression (recall) and calculate its value for any given state of a system.
- Over time, the value of the reaction quotient Qr tends to the equilibrium constant K (criterion for spontaneous change).
- Illustration of the test on acid-base reactions and redox reactions.
 

 

Batteries, devices involving spontaneous transformations to recover energy

- Spontaneous transfer of electrons between chemical species (mixed or separated) for two couples oxidative / reductive type of metal ion / metal, Mn+ / M(s).
- Establishment and functioning of a cell: observation of the direction of flow of electricity, moving charge carriers, the role of salt bridge, electrode reactions.
The battery system off balance in its functioning as a generator.
During the spontaneous evolution, the value of the quotient of reaction tends to the equilibrium constant. Cell balance "dead battery" maximum amount of electricity charged in a circuit.
- Electromotive force of a battery (emf) E: measurement, electrode polarity, direction of current flow (related to the physics course).
- Example of conventional battery.

 

Examples of changes forced

- Identification of experimental possibility, in some cases to change the direction of evolution of a system by applying a current in the opposite direction to that observed when the system evolves spontaneously (forced transformation).
- Reactions to the electrodes, anode and cathode.
- Application to electrolysis: principle and examples of common applications and industries.

 

 

 

- How to control the chemist does the transformations of matter?
Examples from the engineering and the life sciences

 

The reactions of esterification and hydrolysis

- Formation of an ester from an acid and an alcohol, write the equation of the corresponding reaction called esterification reaction.
- Hydrolysis of an ester, write the equation of the corresponding reaction.
- Identification of experimental steady state during transformations involving reactions of esterification and hydrolysis.
- Definition of the performance of a transformation.
- Definition of a catalyst.
- Control the speed of reaction temperature and catalyst.
- Control of the final state of a system: an over-reactive or disposal of a product.

 

Examples of monitoring the evolution of chemical systems made in the chemical industry and in the life sciences
 

- Change of a reagent
Synthesis of an ester from an acid anhydride and an alcohol.
Basic hydrolysis of esters: application to the saponification of fatty substances (preparations and properties of soap, structure-properties).

- Using catalysis
Homogeneous catalysis, heterogeneous enzyme: selectivity of the catalysts.

 

 

- Extract and identify chemical species

 

Mining
- Eugenol in the clove.
- Citral and limonene in lemon peel, orange in the leaves
verbena.
- Trimyristin in the nutmeg.
- Gallic acid in powder Tara.
Chromatography (adsorption and shares) thin layer on paper or column (Pasteur pipette) (1 meeting)
- Food coloring in a syrup, a soft drinks or a candy.
- Dyes paprika.
- Sugars in fruit juice.
- Identification of the active ingredients in a drug
(Aspirin, paracetamol and caffeine).
- Analysis of a brass.
- Amino acids, hydrolysis products of aspartame.
- Pigments in green plants (spinach, sorrel, etc.).

 

- Create and reproduce the chemical species

- Preserving Food: benzoic acid.
- Food coloring: amaranth.
- Aroma: vanilla.
- Synthesis of an imine having the properties of a liquid crystal.
- Synthesis of an amide analgesic: acetaminophen.
- Synthesis of a polyamide: nylon.

 

 

- Perform quality control

 

- Calibration

- Iron Ions in a wine or a tape.
- "Chlorine" in pool water.
- Food coloring in confectionery.
- Copper in brass.
- Methylene blue in eye drops.

 

- direct titration (d), indirect (i)

 

Redox reaction

- Vitamin C in lemon juice (or d i).
- Ethanol in wine (i).
- Hydrogen peroxide officinale (d).
- Bleach (i).
- Total sulfur dioxide in white wine (i).
- Iron Ions in a crop protection product, a mineral or a magnetic strip (i).

 

Acid-base reaction

• direct titration monitored by pH meter or indicator end of the reaction.
• Titration of acid
- Lactic acid in milk.
- Vitamin C in one tablet.
- Acid value of oil.
• Base Titration
- Hydrogen ions in a mineral water or a solution
infusion pharmacy.
- Ammonia drugstore.

 

Other reactions

 

Reaction of precipitation

• Complete Flag Response
- Chloride ions in water or in a moisture absorber (d).
- Silver ions in a paper or photographic film (d).
• Conductivity
- Chloride ions in a mineral water (d).
- Sulfate ions in a mineral water (d).
- Heavy metals in wastewater (silver ions, lead ions (II), etc..) (D).

 

Reaction complexation with terminator reaction

- Calcium and magnesium ions in a mineral water (d).
- Calcium ions alone in a mineral water or in an absorber
humidity (d).

 

Other

- Iodine value of oil (unsaturated) by the Wijs reagent (i).

 

- Develop a "product" consumer: the raw matter in the formulation

 

Separate

Illustrations of some methods used in hydrometallurgical

• Production of an oxide from an ore:

- Alumina, a step in the development of aluminum,
- Titanium dioxide (IV), a step in the development of titanium.

• Separation :

- Iron ions (III) ions zinc (II), a step in the development of zinc,
- Iron ions (III) ions copper (II), a step in the development of copper.

 

Electrolysis

Purify, protect (against corrosion), embellish, recover
• refining of copper.
• Electrolytic deposition:
- Anodized aluminum,
- Electrolytic tin plating of steel
- Electro.
• Recovery of tin (treatment of liquid effluents).

Formulate, package

Retrieval with experimental support wherever possible
- The different formulations of aspirin and paracetamol,
- Food preservatives,
- Food packaging.