Different theories of atomic structure part 1

As we all know that the atom is the smallest  particle of element. Size of the atom are very small less then 100 picometers. Atom consist of three sub atomic particle named as electron (negatively charged) proton (positively charged) neutron (chargeless). There are different theories to explain the structure of atom and arrangement of sub atomic particle in atom. At first the greek philosopher Democritus believed that atoms were indivisible but his ideas didn't agree with later scientific theory.

Dalton Atomic model

John Dalton was a British School teacher published theory of atom in 1808.This was the first modern atomic theory his theory of atomic structure was based on the law of chemical combination

The major postulates of Dalton's atomic theory

1.     Every matter composed of small particles called atoms.

2.     Atoms of the same element are similar in shape and mass, but differ from the atoms of other elements.

3.     Atoms can nither be created or nor be destroyed.

4.     Atoms of different element may combine with each other in a fixed,simple,        whole number ratios to form compound atoms.

5.     The atom is the smallest unit of element and can take part in a chemical reaction.

Drawabacks of Dalton atomic model

1.     This theory didn’t explain about the sub atomic particle electron, proton and neutron.

2.     This theory fail to explain about the existence of allotropes.

3.     Fail to explain about the isobars.Fail to explain about isotopes.

Thomsom atomic model

According to thomsom atomic model an atom is a positive sphere in which electorn are embedded like seeds in watermelon. Hence this theory is also called thomsom watermelon atomic model This model had no theoretical and practical justification and was soon discard 

Drawbacks of Thomsom atomic model

. This theory didn't explain about the positively charged particle in atom.

.This theory didn't explain about the stability of atom

.This theory didn't tell us anything about the nucleus of atom.

GENERAL CHEMISTRY PRACTICE

1.which of the following method is neither meant for the synthesis nor for the separation of amines?

a)Hinsberg method                                                                   b)Hofmann method

c)Wurtz reaction                                                             d)Curtuis reaction

2.     Alizarin is used in

a)perfumery                                                                    b)pharmaceutical industry

c)dyeing                                                                         d)food industry

3.     Aspirin is the name of organic compound

a)hydroxyl benzoic acid                                                  b)acetyl salicylic acid

c)phenyl salicylate                                                           d)ethyl salicylate

4.     Which of the following is  polyamide?

a)Rayon                                                                          b)Nylon

c)Terylene                                                                      d)Orlon

5.     Which of the following is insecticide?

a)Bakelite                                                                       b)TNT

c)BHC                                                                            d)Aspirin

6.     How many moles of ammonia can be produced from 8 mole of hydrogen reacting with nitrogen?

a.2.33mole                                                                     b.3.33mole

c.4.33mole                                                                     d.5.33

7.     2gm of O₂ at NTP has volume

a.1.4liter                                                                         b.2.8liter

c.8liter                                                                            d.11.2liter

8.     Isobar have the same number of

a.electrons                                                                      b.protons

c.neutrons                                                                       d.nucleous

9.     Which of the following is not amphoteric substance?

a.NH₃                                                                             b.H₂O

c.HCO₃                                                                          d.HNO₃

10.                        Which of the following shows hydrogen bonding?

a.P                                                                                  b.F₂

c.O₂                                                                                d.NH₃

11.                        Which one of these is weakest?

a.ionic bond                                                                             b.covalent bond

c.metallic bond                                                               d.van der waal’s forces

12.                        Oxidation number of fe in K3[Fe(CN)₆] is

a.+1                                                                                b.+2

c.+3                                                                                d.+4

13.                        In haemoglobin the iron is in

a.+2 oxidation state                                                        b.+1oxidation state

c.+3 oxidation state                                                        d.+4 oxidation state

14.                        The strongest reducing agent is

a.HNO₂                                                                               b.H₂S

c.H2SO₃                                                                              d.SnCl₂

15.                        Which of the following instrument is used for the measurement of atmospheric pressure

a.barometer                                                                     b.nanometer

c.jigameter                                                                      d.manometer

16.                        A real gas show ideal behavior at

a.low temperature and low pressure                               

b.low temperature and high pressure

c.high temperature and low pressure

d.high temperature and high pressure

17.                        A mixture of benzene and toluene forms

a.an ideal solution                                                           b.non-ideal solution

c.suspension                                                                             d.emulsion

18.                        The molarity of pure water is

a.1.16          mole                                                                     b.5.56mole

c.18.36mole                                                                             d.55.56mole

19.                        Which of the following is lewis acid

a.S                                                                                  b.:CH₂

c.(CH₃)₃B                                                                       d.all of these

20.                        Phenolphthalein is not good indicator for titrating

a.NaOH against H2SO₄                                                  b.NaOH against HCl

c.NaOH against oxalic acid                                    d.ferrous sulphate against KMNO₄

21.                        All the element in the group of periodic table have the same

a.atomic number                                                             b.atomic weight

c.no.of valance electrons                                                 d.none of these

22.                        Which of the following has the smallest size

a.Na⁺                                                                                     b.Mg⁺²

c.Al⁺³                                                                             d.F

23.                        Most abundant element in the earth crust is

a.Hydrogen                                                                     b.oxygen

c.silicon                                                                          d.carbon

24.                        Sodium metal cannot be stored in

a.Benzene                                                                       b.Kerosone

c.Alcohol                                                                       d.Alcohol

25.                        Epsom salt is

a.MgSO₄.7H₂O                                                               b. MgSO₄.5H₂O

c. MgSO₄.5H₂O                                                              d. MgSO₄.H₂O

26.                        Which is not an ore of iron

a.haematite                                                                     b.magnetite

c.cassiterite                                                                     d.limonite

27.                        XeF₂ is

a.linear                                                                           b.trigonal planar

c.pyramidal                                                                     d.square planar

28.                        Ammonium cyanate on heating gives

a.urea                                                                             b.Acetamide

c.Hydrazine                                                                    d.Formamide

29.                        Compound having same molecular formula but different properties is called

a.isotopes                                                                       b.isomers

c.isobars                                                                         d.Allotropes

30.                        The compound that doesn’t give a blue colour in lassaigne’s test is

a.Aniline                                                                        b.Glycine

c.Hydrazine                                                                    c.urea

31.                        Nitration of benzene is

a.nucleophilic substitution                                              b.nucelophilic addition

c.electrophilic substitution                                              c.free radical substitution

32.                        Which of the following yield both alkane and alkene

a.kolbe’s reaction                                                           b.willomosn’s synthesis

c.wurtz reaction                                                              d.sandmeyer reaction

33.                        Chloroform can be used in medicine as

a.Anaesthetic                                                                  b.Analgesic

c.Antipyretic                                                                   c.Antibiotic          

Short summary on lipids and there type

                                                         lipids

lipids a group of naturally occurring molecules that include fats, waxes, sterols fat soluble vitamins glycerides diglycerides triglycerides phospholipids and other lipids like fat and oils are important raw material in industries like Vanaspati ghee pant and various industries. the name Leopard originate from Greek word lepos which means of fat. repeat the compound of cell membrane transportation across the cellular membrane. lipids provide insulation for the vital organs protecting them from mechanical shock and in maintaining optimum body temperature. these are the important energy storage compound. glycolipid which means carbohydrate combined with fat and lipoprotein are essential for maintaining Cellular integrity.

some of lipid structure above

classification of lipids

Classified on the basis of their physical properties at room temperature whether they are solid or liquid respectively fats and oils their classification preferable based on their structure. lipids are classified on the basis of their hydrolysis product and also according to the similarities and molecular structure

1) simple lipids

a) fats and oil: this gives fatty acid and glycerol on hydrolysis. who is a liquid at ordinary temperature and contain large amount of unsaturated fatty acid and unit where is fats are solid glycerides of saturated fatty acid. lip is obtained from animal origin they are generally fats and oils are generally obtained from vegetable origin

b) waxes: waxes are the esters of fatty acid and long chain alcohols. waxes gives fatty acid and long chain alcohols on hydrolysis. this provide protective coating on the surface up plants. this coating provides plant from infection, adhesive damage and loss of water on transpiration. example: myricylpalmitate, cetapalmitate.these are used in the preparation of Cosmetic, polishes another Pharmaceutical product.

2) compounds lipid: compound lipids consists of more than two types of structural moieties. phospholipids that is glycerol ester of fatty acid. phospholipid or phosphatides gives fatty acid , glycerol, phosporic acid and a nitrogen containing alcohol on a hydrolysis. example alpha-lecithen, Acephalin etc fatty acid most commonly found in lecithins are palmatic, stearic, oleic,linoeleic and arichidonic acid. brain and nerve tissue are rich in phospholipid.

types of phospholipid.

a)sphingolipids

b)glycolipids

a)sphingolipids: it consists of fatty acid, phosphoric acid sphingosine and an alcohol component on hydrolysis.sphingolipids are commonly believed to protect the cell structure against harmful environmental factor performing a mechanical stable and chemically resistant outer leaflet of the plasma membrane lipid bilayer.

b) glycolipids: hydrolysis of glycolipids Give fatty acid, sphingosine or glycerol and carbohydrate. for example glycolipid found in brain tissue is named as ganglioside.

3) derived lipids:they are the substance produced from the simple and compound lipids through the process of hydrolysis. there are many different types of derived lipids, including alcohol, monoglycerides, diglycerides, fatty acids, terpenes. it is mainly act as hormone

Carbohydrate short basic summary

general introduction on carbohydrate

Carbohydrate are the most important compound which include sugar such as glucose, Fructose and sucrose as well as non sugar Such as starch and cellulose. these are polyhydroxy aldehyde, polyhydroxy Ketone or a compound that can be hydrolysed to them. crystalline substance with sweet taste and soluble in water are called Sugars and substance which are not sweet and insoluble at least soluble in water is called non sugar. carbohydrates are produced in green plants by the process of photosynthesis. it is one of the basic things which are needed by our body.

Basically carbohydrate provide all three basic necessities of life such as food clothes and shelter. chemically carbohydrate content Mainly two functional group, carbonyl group(aldehydeand ketone)and a number of hydroxyl group. accordingly carbohydrates are defined as polyhydroxy aldehyde or polyhydroxy ketone or compound that can be hydrolysed to either of them. carbohydrate at optical active containing more than one asymmetric carbon atom.

fig.structure of carbohydrate.

classification of carbohydrates.

carbohydrate are broadly classified into the following types.

a) monosaccharide

these are the simplest form of the carbohydrate which cannot be further hydrolysed into the simpler unit. the content three, four, five, or six carbon atom and are known as triose,tetrose, pentose or hexose. depending upon whether they contain an aldehyde or Ketone group they may be classified into Aldose and ketose.for example A five carbon aldehyde group called Aldo pentose and 6 carbon mono oxide containing keto group it's called ketohexose.example of monosaccharide.Aldotetrose, ketotetrose, Aldopentose , ketopentose, Aldohexose , ketohexose.

b) oligosaccharides.

oligosaccharide can be hydrolysed into different number of monosaccharide molecule. depending upon the number of monosaccharide that are obtained from them on hydrolysis. they may be called as di-, tri- or tetra-saccharide.

I) Disaccharide: disaccharide give two monosaccharide unit on hydrolysis. it is made by the combination of two monosaccharide. example sucrose

II) Trisaccharide: this givethree monosaccharide unit on hydrolysis.

III) polysaccharide: these are high molecular weight carbohydrate. it gives a large number of monosaccharide unit on hydrolysis .example on starch cellulose