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Reducing agent undergoes 

What And why

Posted by Keerthi s (Jan 19, 2017) (Question ID: 1474)

Why tertiary and secondary amine do not react to carbylamine test 

Posted by Keerthi s (Jan 19, 2017) (Question ID: 1473)

What is peptisation

 

Posted by Kartik Diwale (Jan 19, 2017) (Question ID: 1472)

  • Answers:
  • Peptisation is the process which is the primary cause for the formation of colloidal particles in dispersion medium. It requires an electrolyte known as peptizing agent for the completion of the process. It plays a vital role for understanding precipitation reactions that occur in aqueous solution. It has a number of uses:

    1. It can be used in nano particle synthesis.
    2. It can be used to split large grouping into smaller particles.
    3. It is used for synthesizing Titania.
    4. It helps in filtrating colloidal solution.
    Answered by Naveen Sharma (Jan 19, 2017)
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  • Ans. Peptization is the process responsible for the formation of stable dispersion of colloidal particles in dispersion medium. In other words it may be defined as a process of converting a precipitate into colloidal sol by shaking it with dispersion medium in the presence of small amount of electrolyte.

    Answered by Payal Singh (Jan 19, 2017)
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Effect of demonetization one economy and ppc? (6 marks)

 

Posted by mansi mittal (Jan 19, 2017) (Question ID: 1468)

  • Answers:
  • Ans. Demonetization as a cleaning exercise may produce several good things in the economy. At the same time, it creates unavoidable income and welfare losses to the poor sections of the society who gets income based on their daily work and those who doesn’t have the digital transaction culture.Following are the main impacts.

    1. Demonetization is not a big disaster like global banking sector crisis of 2007; but at the same time, it will act as a liquidity shock that disturbs economic activities
    2. Liquidity crunch (short term effect): liquidity shock means people are not able to get sufficient volume of popular denomination especially Rs 500.  This currency unit is the favourable denomination in daily life. It constituted to nearly 49% of the previous currency supply in terms of value. Higher the time required to resupply Rs 500 notes, higher will be the duration of the liquidity crunch. 
    3. Welfare loss for the currency using population: Most active segments of the population who constitute the ‘base of the pyramid’ uses currency to meet their transactions. The daily wage earners, other labourers, small traders etc. who reside out of the formal economy uses cash frequently. These sections will lose income in the absence of liquid cash. Cash stringency will compel firms to reduce labour cost and thus reduces income to the poor working class.
    4. Consumption will be hit: When liquidity shortage strikes, it is consumption that is going to be adversely affected first.
    5. Loss of Growth momentum- India risks its position of being the fastest growing largest economy: reduced consumption, income, investment etc. may reduce India’s GDP growth as the liquidity impact itself may last three -four months.
    6. Impact on bank deposits and interest rate: Deposit in the short term may rise, but in the long term, its effect will come down. The savings with the banks are actually liquid cash people stored. It is difficult to assume that such ready cash once stored in their hands will be put into savings for a long term. They saved this money into banks just to convert the old notes into new notes. 
    7. Impact on black money: Only a small portion of black money is actually stored in the form of cash. Usually, black income is kept in the form of physical assets like gold, land, buildings etc. Hence the amount of black money countered by demonetization depend upon the amount of black money held in the form of cash and it will be smaller than expected. 
    8. Impact on counterfeit currency: the real impact will be on counterfeit/fake currency as its circulation will be checked after this exercise.
    Answered by Naveen Sharma (Jan 19, 2017)
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What is HVZ reaction?

Posted by jyotika Singh (Jan 19, 2017) (Question ID: 1467)

  • Answers:
  • Ans.Treatment with bromine and a catalytic amount of phosphorus leads to the selective α-bromination of carboxylic acids.

    <h2>Mechanism of the Hell-Volhard-Zelinsky Reaction</h2>

    Phosphorus reacts with bromine to give phosphorus tribromide, and in the first step this converts the carboxylic acid into an acyl bromide.

    An acyl bromide can readily exist in the enol form, and this tautomer is rapidly brominated at the α-carbon. The monobrominated compound is much less nucleophilic, so the reaction stops at this stage. This acyl intermediate compound can undergo bromide exchange with unreacted carboxylic acid via the anhydride, which allows the catalytic cycle to continue until the conversion is complete.

     

    Answered by Payal Singh (Jan 19, 2017)
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  • The HVS (Hell-Volhard-Zelinsky) reaction is an organic reaction used to convert a carboxylic acid with an α-hydrogen and a halogen, to an α-halo carboxylic acid, using a phosphorous catalyst and water.

    The mechanism begins with the reaction of the carbonyl oxygen with phosphorous trihalide to form a P–O bond and release a halide anion. The halide then attacks the carbonyl to form an intermediate which rearranges to release an acyl chloride, an acid molecule, and a phosphine oxide.

    The acyl chloride then tautomerizes to the enol form which subsequently attacks the halogen molecule to form an α-halo acyl halide. Water hydrolysis yields the final α-halo carboxylic acid product.

     

     

    Answered by Naveen Sharma (Jan 19, 2017)
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What is linkage and recombination?

Posted by jyotika Singh (Jan 19, 2017) (Question ID: 1466)

  • Answers:
  • Genetic linkage is the coupling of two genes' patterns of inheritance because they are located on the same chromosome.

    Recombination is any of several processes by which genetic material ofdifferent origins becomes combined. It most commonly occursbetween two sets of parental chromosomes during production of germcells

    Answered by Naveen Sharma (Jan 19, 2017)
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  • Ans.

    Linkage is the tendency of alleles that are close together on a Chromosome to be inherited together during the meiosis phase of Sexual reproduction. Genes whose loci are nearer to each other are less likely to be separated onto different chromatids during Chromosomal crossover, and are therefore said to be genetically linked. In other words, the nearer two genes are on a chromosome, the lower is the chance of a swap occurring between them, and the more likely they are to be inherited together.

    Recombination is the formation of new combinations of genes, either naturally, by crossing over or independent assortment, or in the laboratory by direct manipulation of genetic material.

     

    Answered by Payal Singh (Jan 19, 2017)
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wha will be the effect of gst bill on PPC?

Posted by Muskaan Jain (Jan 19, 2017) (Question ID: 1465)

  • Answers:
  • The Goods And Services Tax (GST) will Effect the Ppc In both Long Run & Short Run . It is good for the long run as it will increase the production potential , gdp of country will also rise and ppc will shift rightward . In short run It will effect the ppc and it will shift leftward as the indirect tax’s will be removed and the supplier will decrease production

    Answered by Naveen Sharma (Jan 19, 2017)
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what is menarch ?

Posted by Anmol Bhatia (Jan 19, 2017) (Question ID: 1464)

  • Answers:
  • Ans. Menarch is the time in a girl's life when menstruation first begins. During the menarche period, menstruation may be irregular and unpredictable. Also known as female puberty.

    Answered by Naveen Sharma (Jan 19, 2017)
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Why LiAlH4 is not reduce keton and NaBH4 is used

Posted by jyotika Singh (Jan 19, 2017) (Question ID: 1463)

  • Answers:
  • Because it is stable compared to LiAlH4, it can be used in aqueous solutions and measured in open air where as LiAlH4 will react violently to moisture and water.

    Sodium  borohydride  is  a  much  less hazardous  reagent  than  lithium aluminum  hydride. The  greater selectivity and  safety  of NaBH4 make  it  the preferred  reagent  in applications with Ketones.

     

    Answered by Naveen Sharma (Jan 19, 2017)
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What is the differential equation of all non horizontal lines in a plane?

Posted by shashank singhal (Jan 18, 2017) (Question ID: 1457)

  • Answers:
  • Solution.

    The general equation of all non-horizontal lines in a plane is ax + by = c, where a ≠0

    Differentiate w.r.t. y, We Get

    adx/dy + b =0

    again differentiate w.r.t. y

    ad2x/dy2 =0

    => d2x/dy2= 0

    this is Required differential equation.

    Answered by Naveen Sharma (Jan 19, 2017)
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Design a training programme for improvement of components of motor fitness.

Posted by Mansi Mishra (Jan 18, 2017) (Question ID: 1454)

What is composition of charge in refining of copper from copper pyrite

Posted by Vikas Yadav (Jan 18, 2017) (Question ID: 1443)

prove that the least perimeter of an isosceles triangle in which a circle of radius r can be inscribed is r.6(3)^1/2

Posted by Vishesh Jindal (Jan 18, 2017) (Question ID: 1442)

  • Answers:
  •  

    Ans.

    ABC is an isosceles triangle with sides AB=AC. O is the center of circle of radius inscribed in the triangle. AD is the altitude,

    So OD=OF=OE=r

    So BD = CD  ............. (1) ( altitude bisect the side)

    BD = BE and CD = CF      .............. (2) ( tangents from the same point are equal in length)

    From (1) and (2) 

    BD=BE=CD=CF ........ (3)

    Similariy AE = AF  ........... (4) (tangents from the same point)

     

    Perimeter of triangle (P) = AB + BC + AC 

    (P) = AE + EB + BD + CD + CF+AF

    (P) = AE + AFEB + BD + CD + CF

    (P) = 2AE + 4BD    (using 3 and 4)

    In Right Triangle OEA, 

    AE = OETan x

    => AE = rtan x 

    => AE = r cot x     .............. (5)

    In Right Triangle ABD

    BD = AD*tanx 

    => BD = (AO + OD)* tan x

    =>BD = rsin x + rtan x

    => BD = r secx + r tanx     ............... (6)

    From 5 and 6 

    => (P) = 2r cotx + 4r(sec x  + tanx)

    => (P) = r ( 2 cotx +4 sec x+ 4 tanx)

    Differentiate w.r.t. x

    we get 

    dPdx = r( -2cosec2x + 4 sec x tan x + 4 sec2x)               ........ (7)

    => dPdx = r( -2sin2x + 4sin xcos2x + 4cos2x)

     

    To find critical value, Put dPdx = 0

    => r( -2sin2x + 4sin xcos2x + 4cos2x) = 0

    => ( -2sin2x + 4sin xcos2x + 4cos2x) = 0

    => -2cos2x + 4sin3x + 4sin2x sin2x ×cos2x  = 0

    => -2(1-sin2x)+ 4sin3x + 4sin2x  = 0

    => -2+2sin2x+ 4sin3x + 4sin2x  = 0

    => -2+ 4sin3x + 6sin2x  = 0

    =>2sin3x + 3sin2x - 1 = 0

    =>(2sin3x + 2sin2x) + (sin2x - 1) = 0

    =>2sin2x(sin x  + 1) + (sinx +1) (sin x - 1) = 0

    => (sin x  + 1) (2sin2x + sin x - 1) = 0

    => (sin x  + 1) = 0  or (2sin2x + sin x - 1) = 0

    => sin x  = -1  is not possible because x cant be more than 90° so  (2sin2x + sin x - 1) = 0

    =>  2sin2x + 2sin x - sin x - 1 = 0

    =>   2sinx( sin x + 1)  -  1( sin x + 1) = 0

    =>  (2sinx-  1) ( sin x + 1) = 0

    =>  (2sinx-  1) = 0 or ( sin x + 1) = 0 

    => sin x  = -1  is not possible because x cant be more than 90° so  (2sin x - 1) = 0

    =>  2sinx-  1= 0 

    =>  sinx = 12

    => x = 30°

    at  sinx = 12 sign changes from -ve to +ve. so it is point of local minima, so at this point value ll be least.

    Hence least perimeter is 

     (P) = r ( 2 cot 30° +4 sec 30°+ 4 tan30°)

    => (P) = r ( 2 3 +4×23+ 4 13)

    => (P) = r  6+ 8+43

    => (P) = r 183

    => (P) = 63r

    Hence Proved

    Answered by Naveen Sharma (Jan 18, 2017)
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Are the following topics added in 2016-17 syllabus??

1. Va de graft generator

2. Human eye

3. GPS (comm. System)

Posted by Supriya Kumari (Jan 17, 2017) (Question ID: 1441)

  • When will I receive my answer??

    Posted by Supriya Kumari (Jan 19, 2017)
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  • Answers:
  • These two (Va de graft generato Human eye) are not in syllabus but GPS (comm. System) is in syllabus. 

    Answered by Payal Singh (Jan 19, 2017)
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Explain  development characteristics during childhood 

Posted by Ashhar Khan (Jan 17, 2017) (Question ID: 1439)

Whatbdo you mean by motor development

Posted by Abhilash Sharma (Jan 17, 2017) (Question ID: 1437)

  • Answers:
  • Motor development means development of child's bones,muscles and ability to move around and manipulate his evnironment.

    Answered by shruti dadhwal (Jan 19, 2017)
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  • Motor development refers to changes in children's ability to control their body's movements, from infants' first spontaneous waving and kicking movements to the adaptive control of reaching, locomotion, and complex sport skills.

    Answered by Naveen Sharma (Jan 17, 2017)
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If A = 1 -1  2   and B = 2   2  -4   

           2  3  4                -4   2  -4

           0  1  2                 2  -1   5

are two square matrix, find AB and hence solve the system of linear equation:

   x - y = 3; 2x + 3y + 4z = 17; y + 2z = 7

Posted by Prabhnoor Singh (Jan 17, 2017) (Question ID: 1433)

  • It's A = 1  -1  0

                 2   3  4

                 0   1  2

    Posted by Prabhnoor Singh (Jan 17, 2017)
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  • Answers:
  • From 1 

    We can say that 

    X = 16BC

    => X = 1622-4-42-42-153177

    => X = 166+34-28-12+34-286-17+35

    => X = 1612-624

    =>X = 2-14

    X = 2 

    y = -1 

    z = 4

     

    Answered by Naveen Sharma (Jan 18, 2017)
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  • Ans.

    A = 1-10234012, B = 22-4-42-42-15

    => AB= 2+4+02-2-0-4+4+04-12+84+6-4-8-12+200-4+40+2-20-4+10

    => AB= 600060006

    => AB = 6I Where I is identity matrix 

    => A-1 = 16B         ........... (1)

     x - y = 3

    2x + 3y + 4z = 17

    y + 2z = 7

    We can represent these eqution In Matrix 

    A= 1-10234012,  X = xyz, C = 3177

    => AX = C=> X = A-1 C

    From 1

    => 

    Answered by Naveen Sharma (Jan 18, 2017)
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Nominal GDP is Rs. 1200 and price index (with base 100) 120, calculate real GDP?

Posted by Nancy Ahuja (Jan 17, 2017) (Question ID: 1429)

  • Answers:
  • Ans. Real GDP = Nominal GDP *100/Price Index 

    Put values 

    Real GDP = 1200*100/120

    => Real GDP = 1000

    Answered by Payal Singh (Jan 17, 2017)
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  • Ans. We Know

    Subsituting the given values,

    => 

    Answered by Naveen Sharma (Jan 17, 2017)
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Discuss the impact of different types of plating surface on athletes & the steps to overcome the impact by avoiding injuries. 

Posted by Varsha Queen (Jan 17, 2017) (Question ID: 1425)

Personality and posture are two opposite sides of same coin.  Comment. 

Posted by Varsha Queen (Jan 17, 2017) (Question ID: 1424)

Nominal GDP can never be less than real GDP. Is it true or false giving reason.

Posted by Nancy Ahuja (Jan 17, 2017) (Question ID: 1422)

  • Answers:
  •  This is False Statement. Nominal GDP can be less than real GDP, if prices in the current year are less than the prices in the base yea

    Answered by Payal Singh (Jan 17, 2017)
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  •  Ans, False: Nominal GDP can be less than real GDP, if prices in the current year are less than the prices in the base year.

    Answered by Naveen Sharma (Jan 17, 2017)
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A window is in the form of a rectangle surmounted by a semicircular opening. The total perimeter of the window is 30m. Find the dimension of the window so as to admit maximum light through the whole window 

Posted by Nancy Agarwal (Jan 16, 2017) (Question ID: 1417)

  • Answers:
  • Ans. Let 2r and x be the lenth and width of the window respectivily.

    Then radius of semicircular portion is r.

    Given : Perimeter of window  = 10cm

    => 

    => 

    Area of window is given by : 

    =>  

    => 

    => 

    => 

    =>  

    Differentiate w.r.t r, we get 

     

     

    To Find critical point, Put 

    => 

    => 

    => 

    => 

    Therefore , by second derivative test, the area is the maximum when 

    Now length of window = 

    Width of Window x =  

    Answered by Naveen Sharma (Jan 17, 2017)
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A window is in the form of a rectangle surmounted by a semicircular opening. The whole perimeter of the window is 30m. Find the dimension of the window so as to admit maximum light through the whole window 

 

Posted by Nancy Agarwal (Jan 16, 2017) (Question ID: 1416)

  • Answers:
  • Ans. Let 2r and x be the lenth and width of the window respectivily.

    Then radius of semicircular portion is r.

    Given : Perimeter of window  = 10cm

    => 

    => 

    Area of window is given by : 

    =>  

    => 

    => 

    => 

    =>  

    Differentiate w.r.t r, we get 

     

     

    To Find critical point, Put 

    => 

    => 

    => 

    => 

    Therefore , by second derivative test, the area is the maximum when 

    Now length of window = 

    Width of Window x =  

    Answered by Naveen Sharma (Jan 17, 2017)
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How a current carrying coil induced emf

Posted by Nityanand Kumar (Jan 16, 2017) (Question ID: 1399)

What do you mean by balanced diet?

 

Posted by shantanu Reang (Jan 16, 2017) (Question ID: 1398)

  • Answers:
  • Balanced diet is the diet which contains variety of food and provide all the nutrients required for the body.Our body require all the nutrients such as vitamins,minerals, proteins, carbohydrates,fats,water and fibre also.

    Answered by shruti dadhwal (Jan 16, 2017)
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Cu+ ion is unstable in aquous solution

 

Posted by Amit Dubey (Jan 15, 2017) (Question ID: 1393)

  • Cu+ ion oxidizes and reduces simultaneously in aqueous solution to give Cu2+ and Cu+ ions. Therefore Cuion is unstable in aqueous solution and it disproportionates readily to Cu2+ and CuIons.

    Posted by Payal Singh (Jan 17, 2017)
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  • Answers:
  • Cu+ ion oxidizes and reduces simultaneously in aqueous solution to give Cu2+ and Cu+ ions. Therefore Cuion is unstable in aqueous solution and it disproportionates readily to Cu2+ and CuIons.

    Answered by Payal Singh (Jan 17, 2017)
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  • In an aqueous medium, Cu2+ is more stable than Cu+. This is because although energy is required to remove one electron from Cu+ to Cu2+, high hydration energy of Cu2+ compensates for it. Therefore, Cu+ion in an aqueous solution is unstable. It disproportionates to give Cu2+ and Cu.

     

    Stability in aqueous conditions depends on hydration energy of ions when they bond to molecules. Cu2+ ions has greater charge density than cu+ ions and hence forms much stronger bonds releasing more energy.

    Answered by Naveen Sharma (Jan 16, 2017)
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  • Cu+ oxidises result in aqueous solution to Cu2+ and Cu. Cu2+ is more stable than Cu+ in aqueous solution as it has high hydration energy than Cu+.

    Answered by shruti dadhwal (Jan 16, 2017)
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What is orthogonal vector 

Posted by Divya Singh (Jan 15, 2017) (Question ID: 1389)

  • Answers:
  • In 2-D or higher-dimensional Euclidean space, two vectors are orthogonal if and only if their dot product is zero, i.e. they make an angle of 90°, or π/2 radians. Hence orthogonality of vectors is an extension of the concept of perpendicular vectors into higher-dimensional spaces.

    Answered by Naveen Sharma (Jan 16, 2017)
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Express the vector a-›=5i^ +2j^+5k^ as the sum of two vectors such that one is parallel to vector b-›=3i^ +k^ and other is perpendicular to b-›

Posted by Prabhnoor Singh (Jan 15, 2017) (Question ID: 1382)

  • Answers:
  • Given  : a =5 i^ + 2j^ + 5 k^ ,  b = 3i^+ k^

    Let Vector a = a1 + a2,  Where a1is parallel to b and a2 is perpendicular to b.

     as a1 is parallel to ba1 = λ(3i+k)=> 3λi+ λk                  ................... (1)

    Also

    a = a1 + a2,

    => a2 = a - a1,

    => a2 = 5i+2j+5k - 3λi-λk

    => a2  = (5-3λ)i + 2j+ (5-λ)k       .................(2)

    As a2 is perpendicular to b

     So, a2·b = 0

     ((5-3λ)i + 2j+ (5-λ)k)  . (3i+k) =0=>  15 - 9λ + 5 -λ = 0=> 10λ = 20 =>λ = 2

    Put value of λ in both equations.

    a1 = 6i+ 2k

    a2 = -i-2j+3k

    Answered by Naveen Sharma (Jan 16, 2017)
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What is the treatment of "interest on short term borrowings" in cash flow statement

Posted by Ritik Garg (Jan 15, 2017) (Question ID: 1379)

The energy of a hydrogen atom in a ground state is -13.6 ev . then what is the k.E of electron in second excited state.

If electron jump from second excited state togramd state.t jen find wavelength of emitted radiation .

Posted by Tanisha Agarwal (Jan 15, 2017) (Question ID: 1377)

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