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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. |
The empirical formula of silicones is analogous to |
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Answer» Alcohols 
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| 2. |
Which of the following is the least thermally stable? |
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Answer» `MgCO_3` |
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| 3. |
What is the difference between van der Waals radius and covalent radius ? |
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Answer» Solution :VAN dar Waals ractius is the RATIO of distance between nucleus of different molecule and 2. While covalent radius is the ratio of distance between of same ATOM and 2. Generally van DER Waals radius `gt` covalent redius |
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| 4. |
Total number of compounds that undero disproportionation redox reaction on heating MnO_(2),HOCI,H_(3)PO_(3),HNO_(2),CrO_(5),HCIO_(3) |
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| 5. |
Which one of the following is non aromatic |
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Answer»
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| 6. |
To which of the following gas mixture, Dalton's Law of partial pressures is not applicable ? |
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Answer» `CO, CO_2` |
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| 7. |
When a crystal of a solute is introduced into a supersaturated solution of the solute : |
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Answer» the SOLUTE dissolves |
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| 8. |
What is water-gas shoift reaction? |
| Answer» SOLUTION :The carbon MONOXIDE of WATER fas can be converted to carbon dioxide by mixing the gas mixture with more STEAM at `400^(@)C` and passed over a shift converter contaiing iron/copper catalysts. This reaction is called water gas shift rreaction `CO+H_(2)OtoCO_(2)+H_(2)uparrow` . | |
| 9. |
Whatis the atomicnumberof carbone? Givethe symbolof its isotops |
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Answer» SOLUTION :Atomic numberof carbon: Z=6 It s threeisotops are`._(6)^(12) C ._(6)^(12)C , _(6)^(14)C` |
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| 10. |
Which of the following is the best reagent to convert 1-Methylcyclohexene into 2-methylcyclohexanol ? |
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Answer» Dil `H_2SO_4` |
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| 11. |
Tincture of iodine is |
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Answer» AQUEOUS SOLUTION of `I_2` |
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| 12. |
What are all the factors that influences electron affinity? |
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Answer» Solution :Factors that AFFECTS electron affinities are size of the atom, effective NUCLEAR charge, SCREENING EFFECT 1. Electron AFFINITY`prop(1)/(" Size of the atom")` 2. Electron affinity `prop`Effective nuclear charge 3. Electron affinity`prop(1)/(" Screening effect")` |
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| 13. |
The region where the probality density function of electron reduces to zero is called………. |
| Answer» SOLUTION :NODAL SURFACE | |
| 14. |
Which out of the following and why can be used to store an alkali metal ? H_2O, C_2H_5OH, Benzene |
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Answer» Solution :Benzene can be used to store an ALKALI METAL because other SUBSTANCES react with alkali METALS as : `Na+H_2O to NaOH + 1/2 H_2` `Na + C_2H_5OH to C_2H_5ONa + 1/2 H_2` |
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| 15. |
Titration curve if a strong base is titrated with srtrong acid is: |
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Answer»
` rArr ` pH INCREASING and jump at neutralization. |
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| 16. |
Which compound undergoes 1,4-addition with Br_2? |
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Answer»
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| 17. |
What are freons ?How are they named ? Give two examples . |
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Answer» Solution :(i) The chloro-fluoro derivates of methane and ethane are called freons . (ii) FREON is represented as freon-cba C = number of C atoms - 1 B= number of H atoms + 1 a = total number of F atoms 
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| 18. |
The volume strength of 1.5 H_(2)O_(2) solutions is |
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Answer» `4.8` |
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| 19. |
Which type of kinetic energy having He, Ne gas ? |
| Answer» SOLUTION :Only ROTATIONAL KINETIC ENERGY. | |
| 20. |
What are intra molecular hydrogen bonding? Explain with an example. |
Answer» Solution :(i) Intra molecular hydrogen BONDS are those which occur within one single molecule. This OCCURS between two 'functional groups within a molecule.  (ii) An intra molecular hydrogen bond joins the OH group to the doubly bonded OXYGEN atom of the carboxyl group on the same molecule. Eg.,Salicylic acid  (iii) Salicylic acid act as an analgesic and antipyretic |
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| 21. |
Which of the following pairs will diffuse at the same rate through a porous plug ? |
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Answer» `CO, NO_2` |
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| 22. |
What is the chromatogram? |
| Answer» Solution :In CHROMATOGRAPHY TECHNIQUE, the COLOURED spots of different compounds DEVELOPED in stationary phase, is called chromatogram | |
| 23. |
Which of the following has the highest value for its radioactivity ? |
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Answer» 1 g of Ra |
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| 24. |
Two isomers (A) and (B) have the same molecular formula C_2H_4Cl_2.Compound (A) reacts with aqueous KOH, gives compound (C) of molecular formula C_2H_4O. Compound (B) reacts with aqueous KOH. gives compound (D) of molecular formula C_2H_6O_2.ldentify (A), (B), (C) and (D). |
Answer» Solution : (i) The COMPOUNDS (A) and (B) with the molecular FORMULA `C_2H_4Cl_2 " are "CH_3-underset(CL)underset(|)(CH)-Cl` and `{:(CH_2-CH_2),(|""|),(Cl""Cl):}`, RESPECTIVELY with IUPAC names: 1, 1-dichloroethane (A) and 1, 2-dichloro- ethane respectively. (ii) 1,1-dichloroethane REACTS with aqueous KOH to give `CH_3CHO`Acetaldehyde as (C). (iii) 1,2-dichloroethane reacts with aqueous KOH to give ethylene glycol `{:(CH_2-CH_2),(|""|),(OH""OH):}` as (D)  
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| 25. |
Which is the following are not state functions ? i)q +w ii) viii) w iv) H-TS |
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Answer» `I,ii and III` |
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| 26. |
The work function for Caesium atom is 1.9 eV. Calculatethe threshold wavelength of the radiation. If Caesium is irradiated with a wavelength 500 nm, calculate the kinetic energy and the velocity of the ejected electron. |
| Answer» SOLUTION :Threshold wavelength `lambda_0=c/V_0=(3xx10^5)/(4.594xx10^14)=6.53xx10^(-7)m=(6.53xx10^(-7))/(10^(-9))nm=653nm` | |
| 27. |
Which of the following containing negative resonance effect? |
| Answer» ANSWER :A | |
| 28. |
Which of the following pairs of compounds are tautomers ? |
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Answer» Propanol & propanone |
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| 29. |
Which is the correct order of increasing energy of the listed orbitals in the atom of titanium ? |
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Answer» 3s 3p 3d 4S Hence, order of increasing energy of orbitals is 3s 3p 4s 3d |
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| 30. |
Which one of the following is an example for free radical initiators? |
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Answer» BENZOYL peroxide |
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| 31. |
When N and S both are present in an organic compound, the sodium fusion extract with FeCl_(3) gives |
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Answer» Green colour |
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| 32. |
Write the preparation of alkene from alcoholes by acidic dehydration. |
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Answer» Solution :Prepare : `R-OH` (alcohol) heated with conc. `H_(2)SO_(4), H_(2)O` molecule is released. Dehydration : Alcohol `(C_(n)H_(2n+1)OH`, where `n gt 1`) treated with conc. `H_(2)SO_(4), H_(2)O` molecule is released, since a WATER molecule is eliminated from the alcohol molecule is eliminated from the alcohol molecule in the presence of ACID, this reaction is known as acidic dehydrogenation of alochols.  reaction : In these reaction -OH group and `beta`-CARBON hydrogen is removed in the form of `H_(2)O` and `pi`-bond is FORMED between `alpha` and `beta`-carbon. These reaction also known as `beta`-elimination reaction. |
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| 33. |
Vapour pressure is the pressure exerted by vapour |
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Answer» in equilibrium with liquid |
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| 34. |
Which of the following arrangements shows schematic alignment of magnetic momentsof antiferromagnetic substances ? |
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| 35. |
Vapour density of a compound is 39. It contains carbon and hydrogen atoms in the ratio 1 : 1. Its molecular formula is |
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Answer» `CH` |
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| 36. |
Which of the following compounds will not exist as resonance hybrid ? Give reason for your answer . R -CONH_(2) |
Answer» SOLUTION :` R-CO NH_(2)` : Can exist as resonance hybrid DUE to the PRESENCE of non-bonding electrons on N and ` PI` -electrons on C = O BOND . 
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| 37. |
Which one is less viscous between HF and H_(2)O ? |
| Answer» Solution :HF, (Each HF MOLECULE is INVOLVED in forming four H-bonds). | |
| 38. |
When 2.4g of carbon reacted with X g of oxygen to form CO and CO_(2), 50.4 kJ of heat was released and no reactant is left over. Standard heats of formation of carbon monoxide and carbon- dioxide are -110.5 kJmol^(-1)and -393.5 kJ mol^(-1)respectively, Calculate X. |
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| 39. |
Which of the following relationship is correct ? |
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Answer» `Delta G ^(0) = -RT LN K` |
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| 40. |
The value of K_(w) at a certain temperature is 6.25xx10^(-14). Calculate the pH of water. |
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| 41. |
What are the oxidation number of the underlined elements in each of the following and how do you rationalise your results? ul(Fe)_(3)O_(4) |
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Answer» Solution :The average OXIDATION number of Fe in `Fe_(3)O_(4)` can be calculated as follows. `overset(x)(Fe_(3))overset(-2)(O_(4))` or `[(x)xx3]+[(-2)xx4]=0` `x=+(8)/(3)` Since, the average oxidation number is fractional, let US consider the STOICHIOMETRY of the molecule. `Fe_(3)O_(4)` is a mixed oxide and has the COMPOSITION `overset(+2-2)(FeO).overset(+3)(Fe_(2))overset(2)(O_(3))`. In `FeO`, the oxidation number of Fe is + 2 while that in `Fe_(2)O_(3)` it is +3. |
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| 42. |
Which of the following pairs of d-orbitals will have electron density along the axes? (NEET Phase - II) |
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Answer» `d_(z)^(2)`,`d_(XZ)` |
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| 43. |
To draw the Lewis structure of covalent molecules/ions following steps are followed: i) Identify the central atom in the given species. Generally central atom is that atom which is less in number, usually electronegativity of central atom is less. Hydrogen is never a central atom ii) Atoms which are directly attached with central atoms are called surrounding atoms. iii) Arrange the surrounding atoms around central atoms and make a single bond between each pair of central and surrounding atoms. If by adoing so the octet of surrounding atoms is not complete, them make double or triple bond to ensure that the octet of all the surrounding atoms is complete, keeping in mind the covalency of central atoms. Usually covalency of any element is the number of unpaired electrons either in ground or in excited state. iv) Covalency of any of the second period element can never exceed four i.e., it can't have more than eight electrons in its valency shell. However, covalency of 3rd and lower period elements can be less than, equal to or greater than four. v) Represent the lone pair of electron particularly of central atom vi) If the given species is polyatomic ion then before making any bond between central atoms and surrounding atoms distribute the charge on surrounding atoms symmetrically as far as possible and then follow all the above mentioned steps. Which of the followrng structures of (CN_(4))^(2-) is incorrect ? |
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Answer»
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| 44. |
What are the oxidation number of the underlined elements in each of the following and how do you rationalise your results? ul(C)H_(3)ul(C)H_(2)OH |
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Answer» SOLUTION :The average oxidation number of C in `CH_(3)CH_(2)OH` can be CALCULATED as follows. `overset(x+1)(CH_(3))overset(x+1)(CH_(2))overset(-2)(O)overset(+1)H` `(x)+[(+1)xx3]+(x)+[(+1)xx2]+(-2)+(+1)=0` or `2x+3+2-2+1=0` or x=-2 Let us consider the structure of `CH_(3)CH_(2)OH` as GIVEN below `H-underset(H)underset(|)overset(H)overset(|2)S-underset(H)underset(|)overset(H)overset(|1)C-O-H` C ATOM labelled as (2) is attached to three H atoms which are less electronegative than C and one `CH_(2)OH` group (O. N. = -1) which is more electronegative than C. Therefore, for this carbon `(+1)+[(+1)xx2]+(x)+(-1)=0` x=-2. |
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| 45. |
Write short note on the following bond parameter . Bond order |
| Answer» SOLUTION :Bond order : The number of bonds formed between the TWO bonded ATOMS in a MOLECULE is CALLED the bond order . | |
| 46. |
What are the oxidation number of the underlined elements in each of the following and how do you rationalise your results? Kul(l)_(3) |
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Answer» SOLUTION :In `Kl_(3)`, the oxidation number of K is +1. Therefore, the average oxidation number of in it will be `-(1)/(3)`. SINCE, the average oxidation number is fractional, let us consider its structure as given below. `K^(+)[l-1larrl]^(-)` The structure reveals that a coordinate BOND is formed between `l_(2)` MOLECULE and `l^(-)` ion. Since, `l_(2)` is is a neutral molecule, the oxidation number of each I atom forming `l_(2)` molecule is zero. The oxidation number of l in `l^(-)` ion is -1. Thus, we have `K^(+)[overset(0)l-overset(0)llarroverset(-1)l]^(-)` |
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| 47. |
What is marine pollution ? |
| Answer» Solution :POLLUTION of sea WATER DUE to discharge of wastes into it is CALLED MARINE pollution | |
| 48. |
What is homolytic cleavage of covalent bond? Explain by example |
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Answer» Solution :In homoltic cleavage, one of the ELECTRONS of the shared pair in a covalent bond goes with each of the bonded atoms. In homolytic cleavage, the movement of a SINGLE electron takes place instead of an electron pair. The single electron movement is shown by .half.headed. (fish hook  ) curved arrow Such cleavage results in the formation of NEUTRAL species (atom or group) which contains an unpaired electron. These species are called FREE radicals. Like carbocations and carbanions, free radicals are also very reactive. A homolytic cleavage can be shown as:  Organic reactions, which proceed by homolytic fission are called free radical or homopolar or nonpolar reactions |
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| 49. |
What are the oxidation number of the underlined elements in each of the following and how do you rationalise your results? H_(2)ul(S)_(4)O_(6) |
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Answer» Solution :The AVERAGE OXIDATION number of S in `H_(2)S_(4)O_(6)` can be calculated as follows. `overset(+1)(H_(2))overset(x)(S_(4))overset(-2)(O_(6))` `(+1)xx2+[(x)xx4]+[(-2)xx6]=0` or `x=+(12-2)/(4)=(5)/(2)=+2.5` Since, the average oxidation number is FRACTIONAL, let us consider the structure of `H_(2)S_(4)O_(6)` as given below. `H-Ounderset((1))(-)underset(O)underset(||)overset(O)overset(||)Soverset(+5)(-)underset((2)) overset(0)S-underset((3))overset(0)S-underset(O)underset(||)overset(O)overset(||)Sunderset((4))-O-H` The oxidation number of S atoms LABELLED as (2) and (3) is zero because they are linked with similar atoms on either sides. Hence, calculating as above, the oxidation numbers of S atoms labelled as (1) and (4) will be +5 each. |
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| 50. |
Write the products A & B for the following reaction. Cl-CH_(2)-CH_(2)-Clunderset(-HCl)overset("Alcoholic KOH")to(A)underset(-HCl)overset("Alcoholic KOH")to(B) |
Answer» Solution :`UNDERSET("1.2-dichloro ETHANE")(Cl-CH_(2)-CH_(2)-Cl)underset(-HCl)OVERSET("Alc. KOH")tounderset((A))underset(("Chloroethane"))(CH_(2)=CH-Cl)underset(-HCl)overset("Alc. KOH")tounderset((B))underset(("ETHYNE"))(CH=CH)`
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