Ionic bonds are formed when an electropositive element react with an electronegative element. The molecules formed due to ionic bond are polar in nature. Some examples are Sodium Chloride & Magnesium Chloride.

Properties of Ionic Molecules 

  1. Hardness: - Since nature of bonding in ionic compound is electropositive and extend in all directions, hence molecules formed by ionic bonding are very hard.
  2. Melting and Boiling Point: - Because ionic bond involves electrostatic force of attraction hence the molecule formed by ionic bond is strong and omnidirectional it involves the breaking of entire lattice, which requires higher energy. Hence melting and boiling point are high.
  3. Conductivity: - They have low electrical conductivity in solid state but are good conductors in molten state because free movement ions in molten state.
  4. Solubility: - Ionic compounds are often soluble in polar solvents such as water. This is due to polar bonding in ionic molecules.
  5. Reactivity: - Due to involvement of ions chemical reactivity of ionic compounds are generally higher.

Structure of Ionic Molecules

Ionic compounds are generally crystalline structure and it is found in solid state at room temperature. Let’s lookat the following picture:-
Structure of Ionic Bonds

Among the above three structures of a molecule having coordination number 3, ‘A’ is most stable as the ions involved are closely packed and the attractive forces very well counter the repulsive forces as the size of cation increases more number of anions are required to stabilize the ionic solid. So, the coordination number also increases therefore radius ratio is an important parameter to determine the structure of the ionic solid. But it suffers various assumptions like molecule is a perfect sphere but in real that is not possible.
Radius Ratio

A molecule with a lower radius ratio value indicates greater stability.
Nowadays a technic known as X-Ray Crystallography is used to determine the complete structure of ionic solid.

Energy Consideration

Lattice Energy:-

The amount of heat released when one mole of lattice is formed from its constituent gaseous ions is known as lattice energy.
Amount of heat absorbed when one mole of lattice is broken to its constituent gaseous ions is known as lattice energy.
Lattice Energy Determination

Born-Haber Cycle

Lattice energy can be determined experimentally by Born Haber cycle, which is based on the Hess’s law of constant heat summation.
Hess’s Law- It states that the energy involved in a particular reaction is same irrespective of the reaction proceeds in one step or via several steps.
Let’s we consider a general reaction of an ionic compound formation:-                          
Born Haber Cycle
From Hess’s law
Hess Law of constant heat summation

Born Lande’s Equation

According to Born Lande’s equation minimum lattice energy is given as follows: -
Born Lande equation
A = Med lung Constant (sum of all geometric interactions)
Z+ & Z- = charges on cation and anion respectively
N0 = Avogadro number
r = Interionic distance
n = Compressibility Factor (Born Constant)

Born Lande’s equation states that lattice energy is directly proportional to product of the charges of cation and anion present in the ionic compound. While it is inversely proportional to interionic distances. For example you can see the change in lattice energy due to change in product of charges and also due to change in interionic distances in following examples.
Ionic molecules comparison

From table ‘A’ we can see that where interionic distance in Lithium Fluoride and Magnesium Oxide are almost same while product of charges is 4 times more in the case of magnesium oxide than Lithium Fluoride hence lattice energy is energy is also approximately 4 fold in the case of MgO. This follows Born Lande’s equation which states that lattice energy is directly proportional to product of charges.
From table ‘B’ we can see that interionic distance is almost four times more in CsI than LiF and hence lattice energy is half in CsI than LiF. This also proves Born Lande’s equation true which states that lattice energy is inversely proportional to interionic distances.                    

JEE Main
JEE Main is an entrance exam conducted by CBSE for admission in to various BE and BTech cources of India's premier institutes such as NITs, IIITs and other Government Funded Technical Institutions including Birla Institute of Technology. Every year around 13 lacs students appear for the exam.While there are 35-40 thousand seats available.So tight your belts to face such a competetive exam.This is also said to be screening test for JEE Advanced which is conducted for admission in to BTech cources of IITs.

How To Apply

There will be only one mode available to apply for the examination and that will be online. You have to first register on the Official Website of JEE Main and then you can fill the online form by logging in to your account. You have to keep your mobile number and an Email ID ready before applying. You should also have your picture in .jpg format and a scanned image of your signatre and thumbprint both also in .jpg format (For boys thumb print should be of left thumb while for girls it should be of right thumb).After filling online application you have to pay application fee. You have three mode to pay your application fee i.e. 
  • Internet Banking, 
  • using Debit/Credit Card and 
  • e-challan. 
Fee details are given below.

Application Fees

JEE Main Syllabus

Correction in Application Form

There will be given a 2 week period after filling online application to correct your mistyped details. Here you should keep in mind rhat you can not change the pattern of exam. So we carefull during the selection of mode of examination i.e. Online/Offline.

Admit Card

Admit card of the exam will be available in the month of March 2016. You can download it from JEE Main website.After downloading admit card you should immediately check details on it. If any discrepencies found quickly contact JEE Main authorities and get it corrected.

Exam Pattern

There are two modes of examination:-

  1. Paper Based Examination(Offline)
  2. Computer Based Examination(Online)
Carefully chose the type of your examination because it can nake or brake your dreams. If you are not given computer based examination earlier than you should never choose this option.But if you comfortable with online mode than you should definately go with it.
The exam will be of 90 questions(30 questions each from Physics, chemistry and maths)of 360 marks.All questions are assigned 4 marks.

Syllabus Of The Examination

You can download JEE Main Syllabus below.Download

Date Of Examination

Exam will be conducted in the first and second week of April 2016.(Expectation)


Result of JEE Main will be declared in the end of April or first week of May 2016(Expected as previous years).

Preparation of All India Rank

After declration of result the All India Rank will be prepared in the end of May or in the first week of June 2016 (This can change because of below given reasons)It is expected that from JEE Main the All India rank will be prepared on the basis of marks obtained by the candidates in the entrance test.Previously it was prepared by giving 40% weightage to 10+2 marks and 60% to the entrance test marks.Now it wil be get scraped if Ministry of Human Resource Department of central government accepts it.The main reason behind scraping the inclusion of 40% board marks is delayed All India Rank preparation and late admission previous year.HOD minister Mrs.Smriti Irani had made a committi of NIT officials to investigate the matter and submit a report.According to reports it supports the scrapping of inclusion of board marks.While some other professors supports current system by saying that it increased the number of girls admission in previous years.Now Mrs. Smriti Irani has made another committie to solve the problem. made If it will be scrapped than it will benefits those students whose board marks are low but he scores well in the entrance exam.[update title="Update@Mesomers" icon="info-circle"]Date-08 November 2015
The HRD ministry has received the recommendations from the Committee of Eminent Person headed by Prof Ashok Mishra that government should abolish the addition of 10+2 board marks from JEE Main 2016 and it also suggested that number of students should be increased from 1,50,000 to 2,00,000 to be eligible for JEE Advanced fom this year.
Othe major recommendations are made that there is a new testing pattern will be launched from  the year 2017 called as National Testing Service which will take aptitude test of students which will be held online twice or thrice in a year. On the basis of performance in this aptitude test 4,00,000 students will be selected for JEE (a common exam for IIT,NIT,IIIT and CFTIs) conducted by IITs. and on the basis of that 40,000+ students will be selected for the admissions in IITs,NITs,IIITs and CFTIs through a common councelling process.  [/update]

Admission Process

It can start in the end of June or  in the first week of July 2016.But admission shedule can not be said appropriately because if 40% weightage will not be scraped than it may take longer in admission processes.

Previous Years Question Papers

Mann Ki Baat
On 25th October 2015 in the All India Radio's 'Mann ki Baat' programme I prime minister Narendra Modi announced  the removal of interviews in the recruitment of non gazetted officers and other service personnel of central government. This decision is taken keeping corruption in mind.
This was most demanded thing from all candidates who prepare for central government jobs. A lot of complaints filed every year regarding biased interviews and demand of money against recomendation during interviewsThis is most welcomed and first major step taken by the government to reduce corruption in the government sector. This decision benifits all students who are preparing for any type 'B', 'C' and 'D' grade jobs of central government jobs. While in gazetted posts (Group'A') it will remain continue. The Government has completed all the processes involved in removal of interviews for low rank jobs of central government. The decision will come in action from 1st January 2016.
Some other highlights of Mann Ki Baat are:-
  • PM Modi given his best wishes to Indian cricket team for deciding(final) match Gandhi Mandela Series between India and South Africa.
  • He promotes organ donation programme Anga Daan, Maha Daan!
  • The he also thanked media for their support in central government's flagship programme Swachha Bharat Abhiyaan.

combined higher secondry level examination 2015
Combined Higher Secondry Level Examination(CGLE) which is also pronounced as SSC(10+2) in common. CHSLE is conducted once in every year by Staff Selection Commission(SSC). CHSLE is conducted once in the end of every year. CHSLE is conducted for induction of Lower Division Clerk(LDC), Data Entry Operator and Postal/Sorting Assistants in the Indian central government offices.


(a) a citizen of India, or
(b) a subject of Nepal, or
(c) a subject of Bhutan, or
(d) a Tibetan refugee who came over to India, before the 1st January,1962,with the intention of permanently settling in India, or
(e) a person of Indian origin who has migrated from Pakistan, Burma, SriLanka, East African countries of Kenya, Uganda, the United Republic ofTanzania(Formerly Tanganyika and Zanzibar),Zambia, Malawi, Zaire,Ethiopia and Vietnam with the intention of permanently settling in India.
Eduatinal Qualification
Name of exam already explains the eligibility of the exam i.e. You have to be 10+2 paseed from any recognised Board or university whether it is state level or national level.
18-27 years on the date of notification of exam. However relaxation is given for the candidates belonging to SC/ST(5years),OBC(3years),PH(10years). For more deatails you can download notification at the end of the page.

How to Apply

There are two modes available for application whether you can apply Online through SSC Website or Offline by post. Posting details are given in the notification.

Application Fees

Application fee for general candidates is Rs.100. Application fee is exempted  for all women candidates and candidates belonging to Scheduled Caste,  Scheduled Tribe, Physically Handicapped and Ex-sevicemen eligible  for reservation, as per Government  orders.

Scheme of the Examination

CHSLE is a two stage selection process which includes a paper based objective type written examination and the other is a typing/skill test.
Written Examination
This is a multiple choice type examination which consists of 200 questions, 50 questions each of General Intelligence/Reasoning, English Language (Basic Knowledge), Quantitative Aptitude(Basic Arithmetic Skill), General Awareness (current afairs & General Knowledge).Time alloted for the exam is 2 hours for normal candidates while it is of 2 hours 40 minutes for VisuallyHandicapped/CerebralPalsy  candidates.

Syllabus of written Examination

General Intelligence:
It would include questions of both verbal and non-verbaltype. The test will include questions onSemanticAnalogy, Symbolic operations, Symbolic/Number  Analogy,  Trends,  Figural  Analogy,  Space  Orientation  ,Semantic Classification,  Venn  Diagrams,  Symbolic/Number Classification,  Drawing  inferences ,Figural  Classification  ,Punched Figural  Patternfolding  and hole/patternfolding    &  unfolding  ,  Semantic  Series, completion,  Number  Series,  Embedded  figures,  Figural Series,  Critical  Thinking,  Problem  Solving,  Emotional  Intelligence,  Word  Building,  Social Intelligence,  Coding  and  decoding,  Other  subtopics,  if  any    Numerical  operations.
English  Language:
Spot  the  Error,  Fill  in  the  Blanks,  Synonyms/Homonyms, Antonyms,  Spellings/  Detecting    Misspelt  words,  Idioms  &  Phrases,  One  word substitution,  Improvement  of  Sentences,  Active/ Passive  Voice  of  Verbs,  Conversion  into Direct/Indirect  narration,  Shuffling  of  Sentence  parts,  Shuffling  of  Sentences  in  a passage,  Cloze  Passage,  Comprehension  Passage.
Quantitative  Aptitude :
Number  Systems:
Computation of Whole Numbers, Decimal and Fractions, Relationship between numbers.
Fundamental arithmetical operations:  Percentages, Ratio and Proportion,  Square roots, Averages, Interest (Simple  and  Compound), Profit and Loss,  Discount, Partnership Business, Mixture  and Allegation,Time and distance, Time and work.
Basic  algebraic  identities  of  School  Algebra and Elementary surds (simple problems) and Graphs of Linear Equations.
Familiarity with elementary geometric  figures  and  facts, Triangle and its vario us kinds of centres, Congruence and  similarity of triangles, Circle and its  chords, tangents, angles subtended by  chords of a circle, common tangents  to two or more circles.
Triangle, Quadrilaterals, Regular  Polygons, Circle, Right Prism, Right Circular  Cone, Right Circular Cylinder,  Sphere, Hemispheres, Rectangular Parallelepiped, Regular Right Pyramid  with triangular or square Base. Trigonometry
Trigonometric ratios, Complementary angles, Height and distances (simple  problems only).
Standard Charts  : 
Use of Tables and Graphs,Histogram,  Frequency polygon, Bar diagram, Piechart.
General  Awareness:
Questions are designed to test the  candidate’s general awareness of the  env ironment around him and its application to society. Questions are also designed to test knowledge of current events and of such matters of everyday observation and experience in their  scientific aspect as may be expected of  an  educated person. The test will also  include questions relating to India and  its  neighbouring countries especially  pertaining to History, Culture, Geography,  Economic Scene, General policy and  scientific research.
For VH candidates of 40% and above visual disability and  opting for SCRIBES there will be no  component of Maps/Graphs/Diagrams/Statistical Data in the General  Intelligence & Reasoning /Quantitative  Aptitude.
Skill/Typing Test
Who qualifies the written part of examination only those can appear in this part of testing. In this stage skill test is taken for Data Entry Operator(DEO) and typing test for Lower Division Clerk(LDC)/Postal or Sorting Assistants. Both the tests are purely qualifying in nature that means this is not included for preparation of selection. You have to only pass this test.

Skill Test

In this test Data Entry Speed of 8,000  (eight  thousand) Key Depressi ons per  hour on Computer is required. The ‘Speed of 8000 key depressions per  hour on Computer’ will be adjudged on the  basis of the correct entry of words/key depressions as per the given passage and the duration of the said Test will be  15 minutes and printed matter in English  containing about 2000-2200 strokes/key depressions would be given to each  candidate who would enter the same in  the  Computer. Visually handicapped  candidates (with 40% disability and  above) will be allowed 35 minutes  including compensatory time 20 minutes  for the skill test.
Typing Test
This test is conducted in English or Hindi only as indicated by candidates in their application form. Candidates who have opted for English medium should have  typing speed of 35 words per minute  and those opting for Hindi medium  should have typing speed of 30 words per  minute.The speed will be adjudged on the accuracy of typing on the Computer of a given text  passage in 10 minutes. Visually  Handicapped candidates (with 40% disability and above) will be allowed 30  minutes.

Admit Card

You can download your admit card when it will be available from below given links according to your region in which you have applied for.
Eastern Region
Kerala Karnataka Region
Sothern Region
Northern Region
North Eastern Region
North Western Region
Madhya Pradesh Region
Western Region
Central Region

Download Previous Years Question Papers

  1. CHSLE Part 1
  2. CHSLE Part 2
  3. CHSLE Part 3
  4. CHSLE Part 4
  5. CHSLE Part 5

Progressive group task
The progressive Group task consists of a set of 4 obstacles which are progressive in nature that means difficulty level increases as you move from start till end. This test is mainly designed to see the candidates reasoning ability and problem solving capability. In this test it is also seen that how you adjust yourself with a group and how you can influence them with your ideas.

How PGT Happens

  • They draw a start line and finish line of white bricks to represent it as natural obstacles like rivers and nallas in the SSB.
  • The area between start line and finish line is placed out of bound for the candidates and the helping material.
  • In this out of bound area some structures are placed.
  • You are provided with helping material in the form of Ballis, planks, ropes and small pieces of wood to help you in crossing the distance from the start line to the finish line.
  • A black box called as load is also provided to you to add to your difficulty level.
Every games has some rules hence this task also has some rules.Listen carefully to the rules as GTO will explain these rules to you only once and these rules will come handy in all the subsequent outdoor tasks.

Rules of Progressive Group Task

The rules involved in progressive group task is given below you should always keep in mind these rules because it will handy in other GTO tasks because these rules are apply to subsequent GTO tasks.
  1. Group Rule:- All the candidates, helping material, and the load must cross first obstacle before you go for the second and subsequent obstacles.
  2. Distance Rule:- Any distance which is vertically and horizontally or diagonally greater than 4 feet, you can’t jump that distance. Instead you have to use helping material you are provided to cross the distance.
  3. Color Rule:-  According to this rule the structure placed in out of bound area but colored as white then it is considered as inbound for you, load and helping material that means you can touch it or place the load or helping material on it. If it is painted red, it is out of bound for all three mentioned above. If it is painted blue than it means that it is inbound for you but it is out of bound for load and helping materials.
  4. Rigidity Rule:- According to this rule no two rigid material can be tied together. Hence if you are provided with plank, balli and rope as helping material and a load, then you can’t tie plank and balli together.
  5. Infinity Rule:- This rule implies that the start line and the finish line should be imagined to be extended to infinity on either side. This means you have to tackle obstacles head on and you can’t walk through the sides of the task.
  6. Final Rule:- The final and most important rule is that if you broken any above given rules than does not panic, just repeat the task again.

Potassium permangnate
Potassium Permangnate 
Indicator is a substance which changes the color in response to a chemical reaction(specially in titrations). It is added to know exact end point for any titration.There are three types of indicators which is discussed below:-
1. Self Indicator:- Basically these are not an indicator it is one of the reacting species of titration(titrant or titrand), which is after completion of reaction changes the color of the solution itself. The best example is Potasium Permangnate(KMnO4) which is a self indicator. After completion of titration the color of solution becomes transpent but when one more drop Potassium Permangnet is added it changes the color of solution to light pink indicating end point of titration.
2.Internal Indicator:- These are those indicators which takes part in the reaction(titration) and after completion of titration it changes the color of the solution indicating the sharp end point. An example of internal indicator is Diphenyl Amine, which is used in the titration of Mohr,s salt and Potassium Permangnate. Some more examples are Methyl Orange, Methyl Red, Phenolphthlein etc
3.External Indicators:- Indicator which never takes part in the original chemical reaction but after completion of reaction it also changes the color of solution to indicate the endpoint. External indicators is not recommended as it leads to loss of some volume of the reaction mixture. One of well known example of external indicator is Potassium Ferricyanide.

What is Group planning Exercise?
In the Group Planning Exercise (GPE) story is explained to you by the Group Testing Officer with the help of a model and story card. This story has 2-3 main problems which is required to solve. It may have a minor problem.
This task passes through 5 stages are as follows:-

  • Stage-1: The GTO will explain a model according to which you have to solve the problems given to you.
  • Stage-2: Then GTO will read the story card.
  • Stage-3: The story card will be given to each candidates for reading and understanding the story. Time assigned to read the story is 5 minutes.
  • Stage-4: The candidate will be given 10 minutes to write the solution on a single sheet of paper.
  • Stage-5: There will be a discussion of about 10-15 minutes on the solution of the problems. After that anyone of you can get up and explain a common group solution of given problems.

Sitting Arrangement: - The arrangement will be made in a hollow square and the model will continue to remain in front of you for the entire duration of the Group Planning Exercise (GPE).

How to Write Solution
First of all mention the aim of your story then write problems arises in between and how you are going to solve the problems and solve these at the same time. Priority of problems should be given as such that the biggest problem comes first and then bigger one then big ones. Use all the resources you found in the model let’s take an example if it is given in the model the incident happened on the road than you should we wise if there is a road than buses, cars or any vehicle surely there available so you can use it to solve your problem. Similarly if there is district headquarter is mentioned than is a hospital will surely exist. These are just common sense.

  • Problem No.1 (Save human life):- First of all solve the problem in which immediate death are going to be happen even if a criminal or terrorist is going to die you have to save their life because life is most precious thing than any.

  • Problem No.2 (Prevent mass/national disaster):- Now write the solution for mass/national disaster which is going to affect a large number of people.

  • Problem No.3 (Any other problem):- Now write the solution of problem which has lesser importance than above problems where life and society is in danger like smuggling, snatching, theft etc.

Before writing solution you should keep all these thing in your mind as follows:-
  • How many candidates are going to solve the problem?        
  • Where they will go?
  • How will they go?
  • What will they do there?
  • At last mention how much distance covered and time consumed to solve the problem.
Never Forget the Aim
Yes, always keep this thing in your mind that never forget to write the compeletion of aim where problems were raised and then solved.
Suggested Video:-
This is an official video of SSB procedure made by Indian Army, watch this one and become more aware of SSB.

Samsung Galaxy S 4  features,price and release date

To smash their competitors Samsung launches the next model of their (Galaxy S) series called Samsung Galaxy S IV.  Samsung doesn’t want to lose their No.1 position in the mobiles market. Their strong competitor Nokia launched earlier their Lumia 920 and 820 with good features and also they launched various Lumia models at an affordable price like Lumia (520,610,710) with new and compact Windows 8 operating system. On the other hand
Apple’s iPhone 5 also became the best selling phone of the world in 2012 by defeating Samsung’s Galaxy S III. So, now Samsung wants to conquer their competitors hence, they are now come with many big hardware specifications.

Popular Posts Widget Customizations For Blogger
Demo Of Customization
To become a real Pro Blogger, Of course we should write best and innovative articles but we should also keep eyes on our blog’s look and it’s feel. For every bloggers who wanted to become a professional one, both of the above conditions are mandatory. Most of bloggers in starting period of blogging are harassed by many blogging guide blogs or websites by giving wrong ideas. They also force to give credits for every widgets, that is not necessary and it also gives a bad image to newbie blogger.
So, I have started a series of Articles on Customization of blogger template(s), which will surely help you to create a unique comprehensive design for your blog. And you don’t have to give credits for it. In this post we will customize blogger’s default Popular Posts Widget.

It may not be necessary to say that the Samsung Galaxy Note 3 rumors, specs and release date don’t come on same day. Rather, a clear picture of what is expected to come is generated after considering some leaks all over the place. For now, let’s check out our preview on SamsungGalaxy Note release date, rumors and specs.

Release Date of Samsung Galaxy Note 3 :-
Samsung hasn’t officially announced the release date for the new Samsung Galaxy Note 3. However, there are some possible rumors doing to rounds as to when it shall be launched. The Korean Times was the one to start the rumor at first. The Korean Times stated that the Note 3 will be available in the market in 2013. According to the Korean Times the Galaxy Note 3 will definitely come this year.
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