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This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
What are ionic hydrides |
| Answer» Hydrogen can combine with elements in three ways 1. When it looses its electron (with Metals ) 2. When it gains an electron (with non metals). 3 by electron sharing or covalent bond with C Since metals have tendency to loose their electron they for + ions eg Na+ or K+. When hydrogen combine with these metals it forms hydrides.Eg: NaH sodium hydride or KH potassium hydride. So basically hydride is H - ion . Hydrogen ion with negative charge. | |
| 2. |
huckel\'s law explain |
| Answer» The law obeyed for the aromatic conditions | |
| 3. |
B2h6 andC2h6 have same molecular formula but different stucture why? |
| Answer» Because they show isomersim. | |
| 4. |
What is hyperconjugation with examples |
| Answer» It is delocalisation of sigma bond | |
| 5. |
Why lindlar catalyst only give cis compounds |
| Answer» | |
| 6. |
Why alkyl group act as electron donor when attached to a pi system |
| Answer» Becoz of hyperconjugation . Carbon have slightly higher electron density than hydrogen | |
| 7. |
Explain optical isomerism with examples |
| Answer» | |
| 8. |
C6H14 has got five isomers and C7H16 has nine. But why? |
| Answer» Chaining depends upon no. of C atoms in molecule. | |
| 9. |
Tutors are requested to please teach us slowly and clearly... |
| Answer» | |
| 10. |
State hunds rule |
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Answer» Electron pairing in s,p,d and f orbital can not occur until each orbital of a given subshell contain one electron or its singly filled Kv ki ho |
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| 11. |
Shape of sp3d3 orbitals |
| Answer» | |
| 12. |
How to reduc density of mercury |
| Answer» By doing the concentration of mercury in phytoplankton | |
| 13. |
what is the equation for real gas equation??? |
| Answer» Pv=nrt | |
| 14. |
Define hydrolith? |
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Answer» Sorry It\'s hydrolith not hydrolic Hydraulic is a saltlake binary compound used as a reducing agent and the source of hydrogen |
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| 15. |
How can we prepare for school exams for chemistry???? |
| Answer» | |
| 16. |
Write the mechanism of the following reaction . Benzene+HNO3 Conc.HMO3 Conc.H2SO4 Nitrobenzene +H2O |
| Answer» | |
| 17. |
Trans-pent-2-ene is polar while but-2-end is non polar |
| Answer» | |
| 18. |
What is the name of most radioactive element on this planet ? |
| Answer» Franshium | |
| 19. |
What is hybridization ?.. |
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Answer» When two molecular orbitals are combined and form a new molecular orbital It maeans interbmixint |
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| 20. |
IUPAC name ofCH3-C-CH2-CH2COOH || O |
| Answer» Kito-pent- oic acid | |
| 21. |
Why we can\'t separate k2hco3 . |
| Answer» | |
| 22. |
Why it is not possible to prepare k2co3 by solvent process |
| Answer» Because it is too soluble in water | |
| 23. |
Why lithium is strongest reducing agent |
| Answer» reducing nature depends on different factors like sublimation enthalpy , ionisation enthalpy, and hydration enthalpy..since Li has highest hydration enthalpy therefore it strng reducing agent | |
| 24. |
Explain inductive effect |
| Answer» Permanent displacement of electron to staiblised | |
| 25. |
Write a lewis dot structure of oxygen atom and chlorine molecule |
| Answer» | |
| 26. |
Why H2O form hydrogen bond but H2S don\'t from so |
| Answer» Because hydrogen bond forms between hydrogen with oxygen,fluorine&nitrogen only not with another element. | |
| 27. |
How to find hybridisation of long chain organic compounds???????....... |
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Answer» Count the number of bonds prsnt between two carbon atomsIf bond prsnt between them is :-1- single bond =sp3 hybridisation2- double bond = sp2 hybridization3- triple bond = so hybridization Count the number of bond pairs of carbon atom excluding pi bonds |
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| 28. |
Disproportionation reaction |
| Answer» Disproportionation is a chemical reaction typically a Redox reaction where a molecule is transformed into two or more dissimilar products | |
| 29. |
What is dispropotionation reaction |
| Answer» Its a type of redox reaction in which a species reduced and oxidized simultaneously i.e. same element reduce and oxidise , to form two different products.Example: Chlorine gas reacts with dilute\xa0sodium\xa0hydroxide\xa0to form\xa0sodium chloride,\xa0sodium chlorate\xa0and\xa0water.\xa0{tex}3 Cl_2\xa0+ 6 OH^−\xa0\\to 5 Cl^−\xa0+ ClO_3^ −\xa0+ 3 H_2O{/tex}The chlorine gas reactant is in\xa0oxidation state\xa00. In the products, the chlorine in the Cl−\xa0ion has an oxidation number of −1, having been reduced, whereas the oxidation number of the chlorine in the ClO3−\xa0ion is +5, indicating that it has been oxidized. | |
| 30. |
How could Rutherford in his experiment explain nucleus? |
| Answer» | |
| 31. |
Aandhi ka pad parichaya |
| Answer» | |
| 32. |
A radiation emitted from a hot iron is photon or quantum? |
| Answer» Quantum | |
| 33. |
Write application of hess\' law |
| Answer» Application of Hess\'s Law. ... From the knowledge of the standard enthalpies of formation of reactants and products the standard enthalpy of reaction can be calculated using Hess’s law. ... For diatomic molecules like H2, O2, N2, HCl, HF etc | |
| 34. |
The pH of 0.005 M codeine CC18 H21 NO3 sol. Is 9.95 . Calculate it\'s ionization enthalpy and Pkb |
| Answer» From the pH we can calculate the hydrogen ion concentration. Knowing hydrogen ion concentration and the ionic product of water we can calculate the concentration of hydroxyl ions. Thus we have:\xa0[H+] = antilog (-pH)= antilog [-9.95]= 1.12 X 10-10So, [OH-] = Kw / [H+]= (1 X 10-14) / (8.91 X 10-5)= 8.91 X 10-5 MThe concentration of the corresponding codenium ion is also the same as that of hydroxyl ion. Let the codeine ion be denoted by [M+]. ThusKb = [M+][OH-] / [MOH]= (8.91 X 10-5)2 / 0.005= 1.59 X 10-6pKb = -log Kb = - log(1.59 X 10-6)pKb = 5.80 | |
| 35. |
Explain law of mass action |
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Answer» Iss question ko 2 marks h , to Kya aap 2 marks ka answer de sakte h Matlab me kuch smza ni fir se bolo Can u give this answer for 2 marks Law of mass action, law stating that the rate of any chemical reaction is proportional to the product of the masses of the reacting substances, with each mass raised to a power equal to the coefficient that occurs in the chemical equation |
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| 36. |
Why enthalpy of neutralisation is const for strong acod and strong base |
| Answer» Enthalpy of neutralization of is the heat change taking place when 1 gram equivalent of an acid (or base) is neutralized by 1 gram equivalent of base (or acid) in a dilute solution.Heat of neutralization of strong acid-strong base is always constant, i.e. ΔH = -57.1 kj/mole.HCl (aq) + NaOH (aq){tex}\\to{/tex} NaCl (aq) + {tex}H_2O{/tex} (l)...ΔH = -57.1 kj/moleEnthalpy of neutralization of any strong acid (like HCl, HNO3, H2SO4) with a strong base (like LiOH, NaOH, KOH) or vice versa is always the same i.e. 57.1 kj/mol. This is because strong acids, strong bases and salt that they form are all completely ionized in dilute aqueous solutions.Thus the reaction between any strong acid and strong base for example in the above case may be written as :NaOH (aq) + HCl(aq) {tex}\\to{/tex} NaCl (aq) + {tex}H_2O{/tex} (l)... ΔH = -57.1 kj/molethey will dissociate as :Na(+) (aq) + OH(-) (aq) + H(+) (aq) + Cl(-) (aq) {tex}\\to{/tex} Na(+) (aq) + Cl(-) (aq) + {tex}H_2O{/tex} (l)common ions will cancel out..H(+) (aq) + OH(-) (aq){tex}\\to H_2O(l){/tex}Therefore, neutralization is simply a reaction between H(+) ions given by acids and OH(-) ions given by base to form one mole of {tex}H_2O{/tex}.Since strong acid and strong base completely ionize in aqueous solution, the number of H(+) and OH(-) produced by 1 gram equivalent of strong acid and strong base is always the same, hence enthalpy of neutralization between a strong acid and strong base is always constant i.e. ΔH = -57.1 kj/mole. | |
| 37. |
What is borex |
| Answer» It is a white crystalline solid, contains units of tetrahedral shape , dissolve in water and form alkaline solution . Also called as tincal or sodium tetraborate | |
| 38. |
Complete the following chemical reaction pbS(s)+H2O2(aq) |
| Answer» {tex}PbS(s)+4H_2O_2(aq) \\to PbSO_4(s)+4H_2O(l){/tex} | |
| 39. |
Hydrogen peroxide is good oxidizing agent as compare to water . Why ? |
| Answer» Hydrogen peroxide easily decompose to release Oxygen and it acts as a strong oxidizing agent it show oxidizing property in acidic medium as well as basic medium. | |
| 40. |
Hydrogen peroxide is used to store the old oil paintings. why? |
| Answer» Lead oxide is used in lead paintings and Lead statues when they expressed to air for long time lead oxide react with hydrogen sulphide which is found in the air and form lead sulphide which is black in colour when lead sulphide reacts with hydrogen peroxide then white lead sulphide is formed and paintings again comes in its original form | |
| 41. |
What is difference between calcination and roasting? |
| Answer» \tCalcinationRoastingCalcination is a process in which ore is heated in the absence of air or air might be supplied in limited quantityRoasting involves heating of ore lower than its melting point in the presence of air or oxygen.Calcination involves thermal decomposition of carbonate ores.Roasting is carried out mostly for sulfide minerals.During calcination, moisture is driven out from an ore.Roasting does not involve dehydrating an ore.Carbon dioxide is given out during calcinationDuring roasting large amount of toxic, metallic and acidic compounds are released.\t | |
| 42. |
What is empirical formula? In brief |
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Answer» S Can you do by an example of ncert |
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| 43. |
What happen when we heated boric acid |
| Answer» Boric acid is soluble in boiling water when we heat it above 170 degree C it further dehydrates and form metaboric acid Metaboric acid which is sparingly soluble in water it is heated upto or above 300 degree C It further dehydrates | |
| 44. |
Limitations of wurtzz reaction |
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Answer» @Odd no of alkanes can\'t be made from this reaction@Methane can\'t be made by this reaction Unsymmetrical alkane cannot be produced by this method |
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| 45. |
Define law of multiple proportion |
| Answer» When two elements combine with each other to form two or more than two compounds,the masses of one of the elements which combine with a fixed mass of the other.bear a simple whole number ratio to one another. | |
| 46. |
Why gallium is less atomic radius then that of aluminum |
| Answer» It has 10-d configuration which have poor shielding effect. Hence ts effective nuclear charge is high which contracts the size. | |
| 47. |
Elements that have vacant orbital afer bond formation? |
| Answer» | |
| 48. |
Tommorow is My preboard plz Tell Important topics |
| Answer» The reactions from redox reaction lesson problems from thermodynamics bohrs model lichatliers principle from equilibrium I know only these I hope it helps u | |
| 49. |
Cr2O2- + so2 - cr3+ so2 (acidic medium) half reaction method |
| Answer» | |
| 50. |
What is crystal lattice of metal |
| Answer» | |