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 radius of an atom of an element is 500 pm. If it crystallizes as a face centred cubic lattice, what is the length of the side of the unit cell ? |
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| 2. |
The radius of an atom of an element is 500 pm.If it crystallizes as a face centred cubic lattice, what is the length of the side of the unit cell ? |
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| 3. |
A thin wire has a length of 21.7 cm and radius 0.46 mm. Calculate the volume of the wire to correct significant figures. |
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| 4. |
The radioactive isotope of hydrogen is |
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Answer» `""_(1)^(1)H` |
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| 5. |
The radioactive isotope of hydrogen is called ……….. And its nucleus contains ……….. Proton and ……….. Neutrons. |
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| 6. |
The radioactive element of group 2 element is_________ |
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Answer» Strontium |
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| 7. |
Theradii of the F, F^(-) , O " and " O^(2-) are in the order …. |
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Answer» `O^(2-) GT O gt F^(-) gt F` |
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| 8. |
The radii of Na^(+) and Cl^(-) ions are 95 pm and 181 pm respectively. The edge length of NaCl unit cell is |
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Answer» 276 PM =`2times"Destance between NA^(+) and Cl^(-)ions` =`2(r_(Na+)+r_(Cl-))=2(95+181)`pm. ltbrge552 pm. |
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| 9. |
The radii of maximum probability for 3s, 3p and 3d electrons are in the order : |
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Answer» `(r_("MAX"))_(3d) gt (r_("max"))_(3p) gt (r_("max"))_(3s)` |
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| 10. |
The radii of F, F^(-), O, O^(2-) are in the order |
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Answer» `O^(2-) GT F^(-) gt O gt F` |
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| 11. |
The radii of F, F^(-) , O andO^(2-)are in the order |
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Answer» `O^(2-)gtOgtF^(-)GTF` |
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| 12. |
The radical halogenation of 2-methylpropane gives two products: (CH_(3))_(2)CHCH_(2)X (minor) and (CH_(3))_(3)CX (major) Chlorination gives a larger amount of the minor product than does bromination, why? |
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Answer» Bromine is more reactive than chlorine and is able to ATTACK the LESS reactive `3^(@)C-H` |
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| 13. |
The radical halogenation of 2 - methyl propane gives two products (CH_(3))_(2)CHCH_(2)X_("(minor)") and (CH_(3))_(3)CX_("(major)"). Chlorination gives larger amount of the minor product than the bromination because |
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Answer» Bromine is more REACTIVE than chlorine and is able to attack the less reactive `3^(@)C-H` Bromine is less reactive, more selective |
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| 14. |
The radical halogenation of 2-methyl propane gives two products (CH_(3))_(2)CHCH_(2)X_(("minor")) and (CH_(3))_(3)CX_(("major")). Chlorination givs larger amount of the minor product than the bromination because |
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Answer» BROMIDE is more reactive than chlorine and is able to attack the less reactive `3^(@)C-H` |
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| 15. |
The radiation with highest wave number |
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Answer» Microwaves |
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| 16. |
The radial probability distribution curve of an orbital of H has '4' local maxima . If orbital has 3 angular node then orbital will be : |
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Answer» 7 f |
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| 17. |
The radial probability distribution curve obtained for an orbital wave function has 3 peaks and 2 radial nodes. The valence electron of which one of the following metals does this wave function correspond to ? |
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Answer» Cu |
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| 18. |
The radial distribution function [P(r)] is used to determine the most probable radius, which is used tofind the electron in a given orgital (dP(r))/(dr) for 1s-orbital of hydrogen like atom having atomic number Z, is (dP)/(dr) = (4Z^3)/(a_0^3) (2r-(2Zr^2))/(a_0) e^(-27 x//a_0) : Then which is the following statements is/are correct ? |
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Answer» At the point of maximum value of radial distribution function `(dP(r))/(dr)=0`, one anti-node is PRESENT `(2r - (2Zr^2)/(a_0))= 0,r =(a_0)/(Z)` Where Z = 3 for `Li^(2+)` and Z= 2FOR the `He^+` , Z=1 for hydrogen. |
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| 19. |
The radial distribution function [P(r)] is use to determine the most probable radius, which is used to find the electron in a given orbital (dP(r))/(dr) for 1s-orbital of hydrogen like atom having atomic number Z, is (dP)/(dr) = (4Z^(3))/(a_(0)^(3))(2r-(2Zr^(2))/(a_(0)))e^(-2Ze//a_(0)). Then which of the following statements is/are correct |
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Answer» At the point of maximum value of radial distribution function `(dP(R))/(dr) = 0`, ONE antinode is PRESENT |
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| 20. |
The R/S conifiguration of these compounds are respectively |
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Answer» R,R,R |
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| 21. |
The questionsgiven belowcontainstatement -1 (Assertion ) andstatement -2 (Reason ) . Ithas fouroptions(a), (b) , ( c) and (d ) out ofwhich ONLYONE iscorrect . Choosethe correctoptionas.Statement -1 . Of all theelementsheliumhas thehighestvalue offirstionizationenthalpy Statement-2Heliumhas themostpositiveelectrongainenthalpyof all theelement s. |
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Answer» Statement -1 ISTRUE Statement-2 isTrue, Statement-2 iscorrectexplanationfor Statement -5 |
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| 22. |
The questionsgiven belowcontainstatement -1 (Assertion ) andstatement -2 (Reason ) . Ithas fouroptions(a), (b) , ( c) and (d ) out ofwhich ONLYONE iscorrect . Choosethe correctoptionas. Statement - 1. The ionicsize ofO^(2-) is biggerthan that ofF^(-)ion. Statement -2. O^(2-) and F^(-) are isoelectronic ions. |
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Answer» Statement -1 ISTRUE Statement-2 isTrue, Statement-2 iscorrectexplanationfor Statement -3 |
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| 23. |
The questionsgiven belowcontainstatement -1 (Assertion ) andstatement -2 (Reason ) . Ithas fouroptions(a), (b) , ( c) and (d ) out ofwhich ONLYONE iscorrect . Choosethe correctoptionas. Statement -1. The ionicradiifollowsthe order : I^(-)lt I lt I^(+) Statement -2 . Smallerthe valueof z//elargerthe sizeof the species . |
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Answer» Statement -1 isTrue Statement-2 isTrue, Statement-2 iscorrectexplanationfor Statement -4 |
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| 24. |
The R and S configuration for each sterogenic centre in this from top to bottom? |
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Answer» R.R.R |
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| 25. |
The questionsgiven belowcontainstatement -1 (Assertion ) andstatement -2 (Reason ) . Ithas fouroptions(a), (b) , ( c) and (d ) out ofwhich ONLYONE iscorrect . Choosethe correctoptionas. Statement - 1 . The elements having 1 s^(2) 2s^(2)2p^(6)3s^(2) and1s^(2)2s^(2) configurationbelongto the samegroup Statement-2 . Bothhave samenumberof electronselectronsin the valenceshell. |
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Answer» Statement -1 ISTRUE Statement-2 isTrue, Statement-2 iscorrectexplanationfor Statement -2 |
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| 26. |
The questionsgiven belowcontainstatement -1 (Assertion ) andstatement -2 (Reason ) . Ithas fouroptions(a), (b) , ( c) and (d ) out ofwhich ONLYONE iscorrect . Choosethe correctoptionas.Statement -1 . Sixthperiodis the longestperiodin the periodictable. Statement -2 . Sixthperiodinvolvesthe fillingof all theorbitalsof the sixthenergylevel |
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Answer» Statement -1 isTrue Statement-2 isTrue, Statement-2 iscorrectexplanationfor Statement -1 |
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| 27. |
The questions given below consists of an assertion and the reason. Choose the correct option out of the choices given below each question. Assertion (A): If BOD level of water in a reservoir is more than 5 ppm it is highly polluted. Reason(R): High biological oxygen demand means high activity of bacteria in water |
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Answer» Both (A) and R are CORRECT and (R) is the correct EXPLANATION of (A) |
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| 28. |
The quantum numbers of six electrons are given below. Arrange them in order of increasing energies. List if any of these combination (s) has/have the same energy: (i) n = 4, l = 2, m_(l) = -2, m_(s) = -1//2 (ii) n = 3, l = 2, m_(l) = -1, m_(s) = +1//2 (iii) n = 4, l = 1, m_(l) = 0, m_(s) = +1//2 (iv) n = 3, l = 2, m_(l) = -2, m_(s) = -1//2 (v) n = 3, l = 1, m_(l) = -1, m_(s) = +1//2 (vi) n = 4, l = 1, m_(l) = 0, m_(s) = +1//2 |
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Answer» Solution :The ORBITALS occupied by the ELECTRONS are (i) 4D (ii) 3d (iii) 4P (iv) 3d (v) 3p (VI) 4p Their energies will be in the order:(v) `lt (ii) = (iv) lt = (iii) lt (i)` |
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| 29. |
The quantum numbers of six electrons are given below. Arrange them in order of increasing energies. If any of these combination(s) has/have the same energy lists. (i) n = 4, l = 2, m_l = -2, m_s = -1/2 (ii) n = 3, l = 2, m_l = 1, m_s = +1/2 (iii) n = 4, l = 1, m_l = 0, m_s = +1/2 (iv) n = 3, l = 2, m_l = -2, m_s = -1/2 (v) n = 3, l = 1, m_l = -1, m_s = +1/2 (vi) n = 4, l = 1, m_l =0 , m_s = +1/2. |
Answer» Solution : `:. (V) < (ii) = (iv) < (III) = (VI) < (i)` `:. 3p < 3d = 3d < 4P = 4p < 4d.` |
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| 30. |
The quantum numbers of six electrons are given below. Arrange them in order of increasing energies. Do any of these combination have same energy. {:(1.,n=4,l=2,m_(l) = -2,m_(s)=-1//2,),(2.,n=3,l=2,m_(l) = 1,m_(s) = +1//2,),(3.,n=4,l=1,m_(l) = 0,m_(s) = +1//2,),(4.,n=3, l=2,m_(l) = -2,m_(s) = -1//2,),(5.,n=3,l=1,m_(l) = -1,m_(s) = +1//2,),(6.,n=4,l=1,m_(l) = 0,m_(s) = +1//2,):} |
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Answer» SOLUTION :The order or increasing energies is : `5<2 =4<3 = 6<1 ` 2 and 4 electrons have the same ENERGY, similarly 3 and 6 electrons also have same energy |
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| 31. |
The quantum numbers of four electrons (e_(1) " to " e_(4)) are given below : {:(,n,l,m,s,,,n,l,m,s),(e_(1),3,0,0,+1//2,,e_(2),4,0,0,+1//2),(e_(3),3,2,2,-1//2,,e_(4),3,1,-1,+1//2):} Correct order of decreasing energy of these electrons is |
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Answer» `e_(4) gt e_(3) gt e_(2) gt e_(1)` |
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| 32. |
The quantum numbers n=2, l=1 represent |
| Answer» Solution :l=1 is for p orbital | |
| 33. |
The quantum number which tells about the orientation of different orbitals of an atom is called........ |
| Answer» SOLUTION :MAGNETIC QUANTUM NUMBER | |
| 34. |
The values of quantum numbers n, 1 and m for the fifth electron of boron is |
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Answer» rotation of the electron in clockwise and anticlockwise direction RESPECTIVELY. |
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| 35. |
The quantum number which may be designated by s,p,d and f instead of number is |
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Answer» <P>n |
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| 36. |
The quantum number which tells about the angular momenta of the different electrons present in an atom is called........ |
| Answer» SOLUTION :AZIMUTHAL QUANTUM NUMBERS | |
| 37. |
The quantum number which explain the line spectra observed as doublets in case of hydrogen and alkali metals and doublets & triplets in case of alkaline earth metals is |
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Answer» Spin |
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| 38. |
The quantum number which is equal for all the d-electrons in an atom is |
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Answer» l |
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| 39. |
The quantum number of sixelectrons are givenbelow,Arrangethemin orderof increasingenergies . If anyofthesecombinationhashave thesameenergylists:(1) n-4,l=2 , m_(1)= 2m_(1) = (1)/(2) (2)n=3, l = 2, m_(1)= 1 ,m_(s) = (1)/(2) (3 ) n=4, l = 1 , m_(1) = =0 m_(s ) = (1)/(2) (4 )n=3: l= 2 m_(1)= - 2 m_(s ) = - (1)/(2) (5 )n=3, l = 1,m_(1)= - 1m_(s ) = (1)/(2) (6)n=4, l = 1, m_(1)= 0m_(s ) = (1)/(2) |
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Answer» SOLUTION :(1)L =2so dand n= 4 so4dsubshell (2)l=2so dand n=3 so3dsubshell (3 )l =1so p andn=4so 4p (5 )l =1 sop andn= 3 so 3p (6)l =1so p andn=4so 4p This4d3d , 3d4parrange as perenergythan (5) `3p(4 ) 3d = 2 (3d)lt (6) 4p= (3) 4p lt (1)4D (5 )lt (4) = (2)lt (6)= (3) lt (1) to`energyincreases(2) ,(3) (4) and(6) has sameenergy . |
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| 40. |
The quantum number not obtained from the Schrodinger.s wave equation is |
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Answer» n |
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| 41. |
The quantium number of four electrons (e_1to e_4) are given below The correct order of decreasing energy of these electrons is |
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Answer» `e_4 gt e_3 gt e_2 gt e_1` |
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| 42. |
The quantity that does not change for a sample of a gas in a sealed rigid container when. It is cooled from 120^(@)C to 90^(@)C at constant volume is: |
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Answer» average energy of the molecule |
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| 43. |
The quantity of heat required to raise the temperature of 1 gm of water by 1^@C is ____ |
| Answer» SOLUTION :1 CALORIE | |
| 44. |
The quantim mechanical treatment of the hydrogen atom gives the energy vale:E_n=(-13.6)/(n^(2))eV "atom"^(-1)(i) use thios expression to find /_\Ebetween=3 and n=4(ii) Calcuilate the wavelength corresponding to the above transition. |
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Answer» Solution :(i) When n=3 `E_3=(-13.6)/(3^(2))=(-13.6)/(9)=-1.511eV "atom"^(-1)` When n=5`E_4=(-13.6)/(4^(2))=(-13.6)/(16)=-0.85 eV "atom"^(-1)` `/_\E=E_4-E_3` `=-0.85-(-1.511)=+0.661eV "atom"^(-1)` `/_\E=E_3-E_4` `=-1.511-(-0.85)` `=-0.661 eV " atom"^(-1)` (ii) WAVE length=`gamma ` `/_\E=(hc)/(gamma)` `therefore gamma=(hc)/(/_\E)` `/_\E=0.661xx1.6xx10^(-19)J` `=1.06xx10^(-19)j` h=planck.s constant=`6.626xx10^(-34)JS^(-1)` `c=3xx10^(8)m/s` `therefore gamma=(6.626xx10^(-34)xx3xx10^(8))/(1.06xx10^(-19))` `=1875xx10^(-6)m.` |
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| 45. |
The quality of diesel is expressed in terms of |
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Answer» OCTANE NUMBER |
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| 46. |
The pyknometric density of sodium chloride crystal is 2.165xx10^3 " kg m"^(-3) while its X-ray density is 2.178xx10^3 " kg m"^(-3) . The fraction of the unoccupied sites in sodium chloride crystal is |
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Answer» 5.96 Molar volume from X-ray density `=M/(2.178xx10^3)m^3` `THEREFORE` Volume unoccupied `=M/10^3(1/2.165-1/2.178)m^3=(0.013Mxx10^(-3))/(2.165xx2.178)` `therefore` Fraction unoccupied `=((0.013Mxx10^(-3))/(2.165xx2.178))//((Mxx10^(-3))/2.165)=5.96xx10^(-3)` |
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| 47. |
The pyknometric density of sodium chloride crystal is 2.165times10^(3)kg"" m^(-3)while its X-ray density is 2.178times10^(3)kg"" m^(-3). The fraction of unoccupiedsites in sodium chloride crystal is |
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Answer» `5.96times10^(-3)` `=2.165 times10^(3)KG"" m^(-3)` X-ray density = Calculated density =`2.178 times10^(3) kg"" m^(-3)` DECREASE indensity `=(2.178times10^(3)-2.165times10^(3))kg"" m^(-3)` =`(0.013 times10^(3))kg"" m^(-3)=13kg"" m^(-3)` Fraction of unoccupied sites =`("Decrease in density")/("Calculated density")` =`(13kg"" m^(-3))/(2.178times10^(3)kg"" m^(-3))=5.96times10^(-3)` |
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| 48. |
The pyknometric density of sodium chloride crystals is2.165 xx 10^(3) kg m^(-3)while X -ray density is2.178 xx 10^(3)kg m^(-3) . Thefraction of the unoccupied sites in sodium chloride crystal is |
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Answer» 5.96 ` = M/(2.165 xx 10^(3)) m^(3)` Molar volume from X-ray density ` M/(2.178 xx 10^(3)) m^(3)` Volume unoccpied `M/10^(3) ( 1/(2.165) - 1/(2.178))m^(3) = (( 0.013 M xx10^(-3))/(2.165 xx 2.178))//((M xx 10^(-3))/2.165) = 5.96 xx 10^(-3)` |
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| 49. |
The pyknometer density of NaCl crystal is 2.165xx10^(3)kg m^(-3) while its X - rays density is 2.178xx10^(3)kg m^(-3). The fraction of the unoccupied sites in NaCl crystal is |
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Answer» `5.968` Molar volume from X - RAY density `= (M)/(2.178xx10^(3))m^(3)` `therefore` Volume unoccupied `=((1)/(2.165)-(1)/(2.178))(M)/(10^(3))m^(3)` Fraction unoccupied `=((1)/(2.165)-(1)/(2.178))//(1)/(2.165)` `= 5.96xx10^(-3)` |
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| 50. |
The purpose of chemistry can be understood and described by........... |
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Answer» FUNDAMENTAL PARTICLES |
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