Acid - Base Tritation

 Acid -Base Tritation

It is the branch of analytical chemistry in which acid react with base or alkali or vice versa.
 Acid When acid disslove in water it give Hydrogen ion. 

                 HA---------------------H + A

 Base When base disslove in water it give Hydroxyl ion. 

         BOH-------------------------------B + OH 
When they react with each other , the reaction occuring is,the neutralization of hydrogen ion with hydroxyl ion to form unionized water.
                  H + A + B+OH------------------B + A + water 

                   H+OH----------------------------------Water

 Indicators

 Indicator is a substances with is used for the visual detection and determination oa a specfic consitutient present in any sample. 
Visual detection is a primarily color , but observations of florescence and turbidity are also used.
 Indicator used in all reagents such as Colorimetry Florimetry Turbidimetry.
 Acid base indicator Acid base indicator are organic substance in which acid solution have one color while base or alkaline solution gives different colors. 

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Analytical chemistry

 Analytical chemistry

Analytical chemistry is a science of chemical characterization.
 A complete,characterization of a compound must include both qualitative and quantative analysis.

 Qualitative analysis

 In qualitative analysis , the chemist concerned with the detection or identification of the elements present in a compound. 

Quanitative analysis

 In quanitative analysis, the,relative anount of elements are determined. 
Steps of quantative analysis 
 (1) Obtaining a sample for analysis
 (2) Separation of the desired consitutent
 (3) Measurement, and calculation of result 
(4) Draw conclusion from the analysis.
 Principles of analytical chemistry 
Volumetric Analysis 
Gravimetric Analysis 
Complexometric Analysis 

Importance 

Analytical chemistry should play an important role in the measurement of drugs and metabolites in the field of pharmaceutical sciences. Scientists using analytical techniques to provide quantification of analytes should be familiar with methods for statistically analyzing collected data.

Uses 

Analytical chemistry studies and uses instruments and methods used to separate, identify, and quantify matter.

 

 

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Azimuthal quantum number

Azimuthal quantum number

The azimuthal quantum number is a quantum number for an atomic orbital that determines its orbital angular momentum and describes the shape of the orbital. ... It is also known as the orbital angular momentum quantum number, orbital quantum number or second quantum number.

Symbol

Its symbol is l.

Shapes

In shell s it have a spherical shape.

In shell p it have a dumbell shape.

In shell d it have a cloverleaf shape.

In shell f it have a too complex shape.

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Quantum Numbers

                            Quantum Number

They are four quantum number Which describe the electron in an atom. 

Denoted

 They are denoted by n, l, m s, called the principal quantum number,azimutual quantum number, magnetic quantum number , and spin quantum number, respectively. 

1. Principal Quantum number 

 This quantum number describes the motion of an electron in an orbit and stands for the number of shells or orbits.

 Denoted 

 It is denoted by n. Greater the value of n greater is the volume of bulk of the electron density.

 Integral value

 The  Integral valueof n 1, 2 ,3 ,4......... It take value upto 7 in periodic table in a row.
 The higher value of n correspond to the higher energy, while lower value of n correspond lower energy. 

 Energy levels

 The energy levels L, M, N, O, P, and Q correspond to n= 1, 2, 3, 4, 5, 6, 7 . 

Determination of breaks

The value of n determines the number of breaks and discontinuties in the electron. These breaks are called nodes.
 The value of n describes the binding force and distance between ths nucleus and the orbit in which electron moves.

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Periodic Table

Periodic Table

Dobereiner" Triads

 A german chemist dobereiner observed relationship between atomic masses of several group of three elements called triads. In these group, the central or middle element had atomic mass average of the other two elements. One triad group example is that of calcium(40),strontium (88) and barium(138).

 Newlands Octaves

 After successful determination of correct atomic masses of elements by Cannizzaro in 1860, attempts were again initiated to organize elements. In 1864 British chemist Newlands put forward his observations in the form of law of octaves. He noted that there was a repetition in chemical properties of every eighth element if they were arranged by their incresing atomic masses. He compared it with musical notes . His work could not get much recognition as no space was left for undiscovered element. The noble gases were also not known at that time. 

 Mendeleev,s periodic table

 Russian chemst mendeleev arranged the known elements ( only 63) in order of increasing atomic masses in horizontal rows called periods. So that elements with similar properties were in the same vertical columns. This arrangement was called period table. He put forward the result of his work in the form of periodic law, which is stated as " properties of the elements are periodic function of their atomic masses. Although mendeleev periodic table was the first ever attempt to arrange the elements ,yet it has a few demerits in jt. His failure to explain the position of isotopes and wrong order of the atomic masses of some elements suggested that atomic mass of an elements cannot serve as the basis for the arragements of elements 

Periodic law

 The properties of the elements are the periodic function of their atomic massed. 

Modern Periodic Law 

The physical and chemical properties of element are the periodic function of their atomic numbers. 

Features of the Long Form of periodic Table 

(1) This table is based on atomic number which is a more fundamental properties of the atom.
 (2) The position of an element in the periodic Table is related to its electronic configuration. 
(3) Long form of periodic table reflects more clearly the changes in the properties of various elements while moving across a period from left to right or going down a group.
 (4) The representative and transition elements have been assigned separate position.
 (5) This table also separate metals from non_ metals. 
(6) Hydrogen (H) resembles both the alkali metals as well as the halogens .lt also resemble elements of carbon family. Howeever,it is placed in a separate box just above the group 1,which is not totally correct.
 (7) Helium (He) has been placed at the top of group 18. Noble gases. These are p_ block elements. The outmost orbital of He is s, so its position is not justified.

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Charles Laws

Charles Laws

It is a quanitative relationship between temperature and volume of gas and was given by french scientist J. Charles in 1787.

 Definition

 The volume of the given mass of a gas is ditectly proportional to the absolute temperature when the pressure is kept constant.
                       V proportional T
                              V=KT
                              V/T=K
  If the temperature is changed from T1 to T2 and volume changes from V1 to V2,-then
                         V1/T1=K
                         V2/T2=K 
                       V1/T1=V2/T2
The,ratio of volume to temperature remains constant for the,same,amount of a gas at same pressure. 

 Experimental Verification of Charles Law

 Let is consider a certain amount of a gas enclosed in a cylinder fitted with a movable piston. The volume of the gas is V1 and its temperature is T1. When the gas in the cylinder is heated both volume and temperature of the gas increase. The newest value and temperature are V2 and T2 reSpectively. 
 Here
                             
                                  V1/T1=,V2/T2
 Hence charles law is varified. 

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Graphical Explanation Charles Law

We plot a graph between temperature on x axis and volume of one mole of an ideal gas on y axis. We get a straight line which cuts the temperature axix at _273.16C°. This can be possible only if we extrapolate the graph upto _273.16C°.
 If the substance remain in the gaseous state then we achieve this lowest temperature
. Above this temperature all gases are converted into liquid . If we taken the temoerature on kelvin scale then temperature obey charles laws. 

For example

At 373 k( 100 c°) the volume is,746cm^3 according to charles, law v1/t1= v2/t2= k 566/283= 746/373 = 2= k 

Greater the mass of gases taken, greater will be the slope of straight line. The reason is the greater the number of moles greater the volume occupied. All these straight lines when extrapolated meet at a single point of -273.16 c° ( 0 kelvin). It is apparent that this temperature of -273.16 c° will be attained when the volume becomes zero. But for a real gas the zero volume is impossile which shows that this temperature can not be attained for a real gas. This is how we recognize that -273.16 c° must represent the coldest temperature.

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Liquid and Solid

Matter composition

The existence of matter in our surrounding in the form of gases liquid and solid is xue to difference of interacting forces among the constituent particles.  
There are four forces are mentioned here

1. Dipole dipole force
2.Ion dipole force 
3.Dipole induce dipole force
4.Instantaneous dipole induce dipole force or london despersion 
forces.

 Dipole dipole force

 The positive end of one molecule attract to the negative end of another molecules and these electrostatic force of attraction are called Dipole dipole force.

 Example 

 Hcl ,Chloroform

 Greater the strength of these dipole dipole forces , greater are the value of thermodynamic parameter like melting ,boiling point, heat of vapoirization and heat of sublimation.

 Dipole Induce dipole force 

 The positive end of the polar molecule attracts the mobile electron of the nearby non polar molecules. In this way polarity is created in non polar molecules and both molecules become dipoles. These,are also called Debye forces .

Ion dipole forces

 The force of attraction is present between the ions of the molecules.

London forces

 The momentry force of attraction created between instantaneous dipole and induce dipoleis called london forces. It is present in all types of molecules whether polar or non polar, but it is special for non polar moleculeslike chlorine and hydrogen and noble gases.

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Structure of Atom

 Introduction

 John Dalton

John Dalton said in 1808 that matter is made up of indivisible particle called atoms. Electron and proton are essential part of matter.
 The name electron was proposed by stoney.

 Other Scientists 

Various experiment done by J.J Thomson , GoldStein, Millikan confirmed the divisibility of atom. Millikan, in charge electron. 

Thomson, Model of atom.

 In 1904, J.J Thomson suggested "Plum pudding" model. According to this model an atom consists of a sphere of positive charge in which negative charged particles known as electrons are embedded. The electrons are embedded like the plum in a pudding, as shown in fig(2.1). But this model colud not satisfy the experimental facts and it had to be discarded. 

Rurtherford,s Atomic Model and Discovery of Nucleus.

 Lord Rutherford was a promising physicist of the time. He bombarded a thin sheet of gold of thickness 0.00004 cm with a_ particles. An a_particle is a helium (He) nucleus (He2+). 

A_particles were obtained from a radioactive element radium. A thin lead (Pb) plate with a hole cut in it, served to form a beam of a_particles. A ciricular screen coated with zinc sulphide (ZnS) was placed on the other side of the foil. It was observed by Rutherford that most of the a_particles passed straight through the gold foil. These a_particles caused tiny flashes on the zinc sulphide screen. Very few a_particles one out of ten thousands bounced back in the direction from which they came. Some were deflected at some angles after passing through the gold foil. It was concluded from this experiment that most of the space in an atom is empty. The scatterig of a_particles in all directions further revealed that there is a heavy positive charge at the centre of the atom which causes repulsion. 

 Conclusions of Rutherford,s Model of atom. 

(1) An atom is consisted of two parts I.e., nucleus and extra- nuclear part.
 (2) Nucleus is an extremely small positively charged it is situated at the centre of an atom.
 (3) The electrons which balance the positive charge are distributed in space around the nucleus.

 Defect of Rutherford model

 Rutherford planet like picture was defective and unstisfactory because the moving electron must be accelerated towards the nucleus.
 Therefore, the radius of the orbiting electron should become smaller and smaller and electron should fall into the nucleus . Thus an atomic structure as proposed by Rutherford would collapse. 

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Discovery of Cathode rays

                          Discovery of Cathode rays

Experiment

A gas discharge tube is fitted with two metallic electrodes acting as cathode and anode. The tube is fitted with a gas ,air or vapours of a substance at any desired pressure. The electrodes are connected to a source of high voltage. The exact voltage required depends upon the length of the tube and the pressure inside the tube. The tube is attached to a vaccum pump by means of a small side tube so that the conduction of electricity may be studied at any value of low pressure. It is observed that current does not flow through the gas at ordinary pressure even at high voltage of 5000 volts.when the pressure inside the tube is reduced and a high voltage of 5000_10000 volts is applied, then an electric discharge takes place through the gas producing a uniform glow inside the tube. When the pressure is reduced further to about 0.01 torr, the original glow disappear. Some rays are produced which create fluorescence on the glass wall opposite to the cathode. These rays are called cathode rays. The color of the glow or the fluorescence produced on the walls of the glass tube, depends upon the composition of glass. 

                          Properties of cathode rays 

 1: Cathode rays are negatively charged.

 In 1895 J,perrin showed that when the cathode rays passed between the poles of the magnet , the path of the negatively     

charged particles was curved download to point 2 by the magnetic field.
                         In 1897 , J . Thomson established their electric charge by the application of electric field , the cathode rays were deflected upward ( positive ) to point 3 . Thomson found that by carefully controlling the charge on a plate when the plate and the magnet were both around the tube , he could make cathode rays strike the tube at point 1 .

 2: Production of green florecence 

 They producrme a greenish florecence on striking the wall of the tube . These rays also produce florecence in rare earth and minerals. 

3: Travel on a straight path

 Cathode rays cast a shadow when an opaque object is placed in their path. This proves that cathode rays travel on a,straight line perpendicular to the cathode. 4: Production of X rays Cathode rays can produce X rays when they strike an anode particularly with large atomic mass. 

 5: Production of heat or temperature

 Cathode rays lroduce heat when they falk ob matter e.g when cathode rays from a concave cathode are focussed on a,platinum foil, it being to glow. 6: Cathode rays can ionize gas.

7: They can cause a chemical change, because they have a,reducing effect.

 8: Cathode rays can pass through a thin metal foil like aluminium or gold foil.

 10: The e/m value of cathode rays show that they are,simply electron.

 Conclusion

 J.J Thomson conclude from his experiment that cathode rays consist of a stream of negative charged particles. Stoney named these particles as electron. Thomson also determined the charge to mass ratio (e/m) of electron. He found that e/m value remained the same no matter which gas was used in a discharge tube. He also conclude the all the atom contained electrons. 

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Scales of thermometery

Scales of thermometery

There are three scales of thermometery which are used for temperature messurements. 

Centigrade scale:

                            It has a zero mark for the temperature of ice at one atmosphere pressure. The mark 100 c° indicates the temperature of boiling water at 1 atmospheric pressure. The space between these temperature marks is divided into 100 equal parts and each parts is 1° c.

 Fahrenheit scale:

                              The melting point of ice at 1 atmospheric pressure has a mark 32°f and that of boiling water is 212°f. The space between these temperature marks is divided into 180 equal parts and each part is 1 F.

 Absolute or kelvin scale:

                                         Pressure is 273K. The water boils at 373K or more precisely at 373.16K. Temperature on kelvin scale= Te mperature C+273.16 .

Following relationships help us to understand the interconversion of various scales of temperature.

 K=° c + 273.16 
°c = 5/9[° f-32]
°f,= 9/5 (°c) + 32

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Aliphatic Hydrocarbons

Hydrocarbons

 Hydrocarbons amare organic compound which contain carbon and hydrocarbons.

 Saturated hydrocarbons

 If the valancies of the carbon atoms in a molecules are fully satisfied by a sigma bond. 

 UnSaturated hydrocarbons 

If the valancy of carbon atoms are not fully satisfied by a sigma bond and pi bondis called double or triple bond.

  Alkenes

 Unsaturated hydrocarbons which contain double bond are alkenes

 Alkynes

 Unsaturated hydrocarbons which contain triple bond  are called alkynes. 

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Organic compound

 Organic compound

The Study of compound of carbon and hydrogen and,their derivatives is,called organic compound.
 Classification of organic compound

 (i) Open chain or Alicylic compound 
(ii) Closed chain or cylic compound

 Open chain or Alicyclic chain

                                               The compound in which first and last carbon are not directly linked with each other. It is also called aliphatic compound.

 Straight chain (or non branched ) compound 

                                                                     Those organic compound in which the carbon atoms are connected in series from one to the other. 

 For example

n butane 

Branched chain compound 

                                           Those organic compound in which the,carbon atoms are attached in a series as well as along the side of chain.

  For example

 Isobutylene

 Close chain compound or Cylic compound 

                                                                     The compound in which the first and the last carbon are directly joined with each other.

 a) Homocyclic or carbocyclic compound 

                                                                The compound which the ring consists of only carbon atoms .

 Homocyclic compound are further classified as

 I)Alicyclic compounds 
II) Aromatic compounds

 Alicyclic Compound

The homocyclic compound in which ring consist of three or more carbon atomand resembling aliphatic compounds are called alicyclic compound.

 Formula

 CnH2n 

 Example

 Cyclopropane

 2)Aromatic compound

 The compound in which ring consist of benzene ring , six carbon atom with three alternate double and single bonds.

 Example 

 Benzene 
The aromatic compound may have a side chain or a functional group attached to the ring.

 Example 

 Toluene 

The aromatic compound may also contain more than one benzene rings fused toghter. 

Example 

Naphthalene 

 B) Hetrocyclic Compounds

                                               The compound in which ring consist of more than one kind of atoms are,called hetrocgclic compound or hetrocycles.
 In hetrocyclic compound generally one or more atom of element such as nitrogen, oxygen, or sulphur are present .
 The atom other than carbon viz, N, O , S,present in the,ring is called a betero atom.

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Functional group

Definition

An atom or group of atom or double or triple bond which specifies the properties of organic compound. Six million organic compound are known.

Chemical class	Group	Formula	Graphical Formula	Prefix	Suffix	Example
Acyl halide	Haloformyl	RCOX		haloformyl-	-oyl halide	Acetyl chloride (Ethanoyl chloride)
Alcohol	Hydroxyl	OH		hydroxy-	-ol	Methanol
Aldehyde	Aldehyde	RCHO		oxo-	-al	:Acetaldehyde (Ethanal)
Alkane	Alkyl	RHn		alkyl-	-ane	Methane
Alkene	Alkenyl	R2C=CR2		alkenyl-	-ene	Ethylene (Ethene)
Alkyne	Alkynyl	RC≡CR'		alkynyl-	-yne	Acetylene (Ethyne)
Amide	Carboxamide	RCONR2		carboamidodo-	-amide	Acetamide (Ethanamide)
Amines	Primary amine	RNH2		amino-	-amine	Methylamine (Methanamine)
	Secondary amine	R2NH		amino-	-amine	Dimethylamine
	Tertiary amine	R3N		amino-	-amine	Trimethylamine
	4° ammonium ion	R4N+		ammonio-	-ammonium	Choline
Azo compound	Azo (Diimide)	RN2R'		azo-	-diazene	Methyl orange
Toluene derivative	Benzyl	RCH2C6H5 RBn		benzyl-	1-(substituent)toluene	Benzyl bromide (1-Bromotoluene)
Carbonate	Carbonate ester	ROCOOR			alkyl carbonate
Carboxylate	Carboxylate	RCOO−		carboxy-	-oate	Sodium acetate (Sodium ethanoate)
Carboxylic acid	Carboxyl	RCOOH		carboxy-	-oic acid	Acetic acid (Ethanoic acid)
Cyanates	Cyanate	ROCN		cyanato-	alkyl cyanate
	Thiocyanate	RSCN		thiocyanato-	alkyl thiocyanate
Ether	Ether	ROR'		alkoxy-	alkyl alkyl ether	Diethyl ether (Ethoxyethane)
Ester	Ester	RCOOR'			-oate	Ethyl butyrate (Ethyl butanoate)
Haloalkane	Halo	RX		halo-	alkyl halide	Chloroethane (Ethyl chloride)
Hydroperoxide (see organic peroxide)	Hydroperoxy	ROOH		hydroperoxy-	alkyl hydroperoxide	Methyl ethyl ketone peroxide
Imine	Primary ketimine	RC(=NH)R'		imino-	-imine
	Secondary ketimine	RC(=NR)R'		imino-	-imine
	Primary aldimine	RC(=NH)H		imino-	-imine
	Secondary aldimine	RC(=NR')H		imino-	-imine
Isocyanide	Isocyanide	RNC		isocyano-	alkyl isocyanide
Isocyanates	Isocyanate	RNCO		isocyanato-	alkyl isocyanate
	Isothiocyanate	RNCS		isothiocyanato-	alkyl isothiocyanate	Allyl isothiocyanate
Ketone	Ketone	RCOR'		keto-, oxo-	-one	Methyl ethyl ketone (Butanone)
Nitrile	Nitrile	RCN		cyano-	alkanenitrile alkyl cyanide	Benzonitrile (Phenyl cyanide)
Nitro compound	Nitro	RNO2		nitro-		Nitromethane
Nitroso compound	Nitroso	RNO		nitroso-		Nitrosobenzene
Peroxide	Peroxy	ROOR		peroxy-	alkyl peroxide	Di-tert-butyl peroxide
Benzene derivative	Phenyl	RC6H5		phenyl-	-benzene	Cumene (2-phenylpropane)
Phosphine	Phosphino	R3P		phosphino-	-phosphane	Methylpropylphosphane
Phosphodiester	Phosphate	HOPO(OR)2		phosphoric acid di(substituent) ester	di(substituent) hydrogenphosphate	DNA
Phosphonic acid	Phosphono	RP(=O)(OH)2		phosphono-	substituent phosphonic acid	Benzylphosphonic acid
Phosphate	Phosphate	ROP(=O)(OH)2		phospho-		Glyceraldehyde 3-phosphate

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