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Medical
111 Views   |  

What is the mole fraction of the solute in a 1.00m aqueous solution?

  • Option 1)

    0.177

  • Option 2)

    1.770

  • Option 3)

    0.0354

  • Option 4)

    0.0177

 
As learnt Mole Fraction - -  Mole fraction = Let's assume, we have 1 mole of solute Then, wt. of solvent = 1 kg Moles of solvent = Mole fraction of solute =                                      =                                      = 0.0177 Option 1) 0.177 This option is incorrect Option 2) 1.770 This option is incorrect Option 3) 0.0354 This option is incorrect Option 4) 0.0177 This...
Medical
214 Views   |  

Which of the following is the most correct electron displacement for a nucleophilic reaction to take place?

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

 
As we learnt in Nucleophile - Those e- rich  chemical species having capacity to attack e-deficient portion of substrate. - wherein Nucleophile must have complete octet and atleast one lone pair     Stable due to +I effect of -CH3 group.   Option 1) Incorrect Option 2) Correct Option 3) Incorrect Option 4) Incorrect
Medical
179 Views   |  

Consider the following compounds  

Hyperconjugation occurs in:

  • Option 1)

    II only

  • Option 2)

    III only

  • Option 3)

    I and III

  • Option 4)

    I only

 
As we learnt in Hyperconjugation or ?-? resonance or Baker and Nathan effect - The conjugation between sigma bond and adjacent  multiple bond or carbocation is called Hyperconjugation. - wherein It is permanent effect.    Hyper conjugation can occur only in compound III as it have hydrogen atoms.    Option 1) II only Incorrect Option 2) III only Correct Option 3) I and III Incorrect Option...
Medical
66 Views   |  

Given 

  • Option 1)

    I and III

  • Option 2)

    II and III

  • Option 3)

    I, II and III

  • Option 4)

    I and II

 
As we learnt in Hyperconjugation or ?-? resonance or Baker and Nathan effect - The conjugation between sigma bond and adjacent  multiple bond or carbocation is called Hyperconjugation. - wherein It is permanent effect.       Option 1) I and III Correct Option 2) II and III Incorrect Option 3) I, II and III Incorrect Option 4) I and II Incorrect
Medical
530 Views   |  

The electrolytic reduction of nitrobenzene in strongly acidic medium produces:-

  • Option 1)

    Azooxybenzene

  • Option 2)

    Azobenzene

  • Option 3)

    Aniline

  • Option 4)

    p-Aminophenol

 

p-aminophenol

Medical
89 Views   |  

In the extraction of copper from its sulphide ore, the metal finally obtained by the reduction of cuprous oxide with:

  • Option 1)

    iron (II) sulphide

  • Option 2)

    carbon monoxide

  • Option 3)

    copper (I) sulphide

  • Option 4)

    sulphur dioxide

 
  Reduction of Metal Oxide to Metal - The crude metal is obtained when the roasted ore or calcined ore is put to reduction by using a suitable reducing agent. - wherein HgO+HgS 3Hg+SO2     Option 1) iron (II) sulphide Incorrect Option 2) carbon monoxide Incorrect Option 3) copper (I) sulphide Correct Option 4) sulphur dioxide Incorrect
Medical
178 Views   |  

In which of the following compounds. the C-Cl bond ionisation shall give most stable carbonium ion?

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

 
  Order of Nucleophilic Substitution Reaction - Reactivity Order - wherein   Tertiary butyl chloride will give the most stable carbonium ion. Option 1) This is correct option Option 2) This is incorrect option Option 3) This is incorrect option Option 4) This is incorrect option
Medical
294 Views   |  

Two stones of masses m and 2m are whirled in horizontal circles, the heavier one in radius \frac{r}{2} and the lighter one in radius r. The tangential speed of lighter stone is n times that of the  value of heavier stone when they experience same centripetal forces. The value of n is:

  • Option 1)

    3

  • Option 2)

    4

  • Option 3)

    1

  • Option 4)

    2

 
As we discussed in concept Force in non-uniform Circular Motion - Ft = mat m = mass ac= centripetal acceleration at = tangen tial acceleration Fc = centripetal force - wherein W is not equal to zero by tangential force. W = 0 by centripetal force         i.e n=2   Option 1) 3 This option is incorrect. Option 2) 4 This option is incorrect. Option 3) 1 This option is incorrect. Option...
Medical
124 Views   |  

A plank with a box on it at one end is gradually raised about the other end. As the angle of inclination with the horizontal reaches 30^{o} the box starts to slip and slides 4.0m down the plank in 4.0s. The coefficients of static and kinetic friction between the box and the plank will be, respectively:

  • Option 1)

    0.6 and 0.5

  • Option 2)

    0.5 and 0.6

  • Option 3)

    0.4 and 0.3

  • Option 4)

    0.6 and 0.6

 
As we discussed in concept Angle of Friction - Angle  is called angle of friction. R = Reaction,        Force of limiting friction - wherein  static friction coefficient Angle made by resultant of limiting friction and R with the normal reaction.       Option 1) 0.6 and 0.5 This option is correct. Option 2) 0.5 and 0.6 This option is incorrect. Option 3) 0.4 and 0.3 This option is...
Medical
186 Views   |  

Two spherical bodies of mass M and 5 M and radii R and 2R released in free space with initial separation between their centres equal to 12 R. If they attract each other due to gravitational force only, then the distance covered by smaller body before collision is

  • Option 1)

    4.5 R

  • Option 2)

    7.5 R

  • Option 3)

    1.5 R

  • Option 4)

    2.5 R

 
As we learnt Properties of Gravitational Force - (i) Always attractive (ii) It is central force (iii) Weakest force   - wherein Ratio of    between two electrons  is  As their centre of mass remains unchanged     or   Option 1) 4.5 R Incorrect Option Option 2) 7.5 R Correct Option Option 3) 1.5 R Incorrect Option Option 4) 2.5 R Incorrect Option
Medical
138 Views   |  

A radiation of energy 'E' falls normally on a perfectly reflecting surface. The momentum transferred to the surface is (C=Velocity of light)

  • Option 1)

    \frac{2E}{C}

  • Option 2)

    \frac{2E}{C^{2}}

  • Option 3)

    \frac{E}{C^{2}}

  • Option 4)

    \frac{E}{C}

 
As we learnt in Momentum of EM wave - - wherein u = Energy of EM wave c = Speed of light in vacuum      For a photon E=PC in case of reflection, change in momentum is 2p  momentum transferred =2p=  Option 1) This option is correct  Option 2) This option is incorrect  Option 3) This option is incorrect  Option 4) This option is incorrect 
Medical
129 Views   |  

The total number of   - bond electrons in the following structure is:

  • Option 1)

    12

  • Option 2)

    16

  • Option 3)

    4

  • Option 4)

    8

 
As we learnt in  Functional group - Atom or group of atom on which almost all chemical properties depend is called functional group. - wherein Above compound has 4- bonds ad 8 bond electrons hence option 4 is correct Option 1) 12 Option is incorrect Option 2) 16 Option is incorrect Option 3) 4 Option is incorrect Option 4) 8 Option is correct
Medical
92 Views   |  

In which of the following compounds, the C - CI bond ionisation shall give most stable carbonium ion ?

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

 
As we learnt in  Application of Hyperconjugation - More is the no of Hyperconjugation  structure more is the stability of carbocation - wherein     Option 1) Incorrect Option 2) Incorrect Option 3) Incorrect Option 4) Correct
Medical
106 Views   |  

In Duma's method for estimation of nitrogen, 0.25 g of an organic compound gave 40 mL of nitrogen collected at 300 K temperature and 725 mm pressure. If the aqueous tension at 300 K is 25 mm, the percentage of nitrogen in the compound is :

  • Option 1)

    16.76

  • Option 2)

    15.76

  • Option 3)

    17.36

  • Option 4)

    18.20

 
As we discussed in Dumas method- Quantitative analyse of nitrogen -   - wherein     m = mass of organic compound P1 = 725 - 25  = 700 mm v1 = 40 ml m = 0.25 g T1 = 300 Option 1) 16.76 This option is correct Option 2) 15.76 This option is incorrect Option 3) 17.36 This option is incorrect Option 4) 18.20 This option is incorrect
Medical
121 Views   |  

Consider the following compounds

Hyperconjugation occurs in:

  • Option 1)

    III only

  • Option 2)

    I and III

  • Option 3)

    I only

  • Option 4)

    II only

 
As we learnt in Hyperconjugation or ?-? resonance or Baker and Nathan effect - The conjugation between sigma bond and adjacent  multiple bond or carbocation is called Hyperconjugation. - wherein It is permanent effect.    Free radicals having Sigma bond undergo hyper conjunction  Option 1) III only This option is correct. Option 2) I and III This option is incorrect. Option 3) I only This...
Medical
589 Views   |  

A mixture of gases contains H2 and O2 gases in the ratio of 1 : 4 (w/w). What is the molar ratio of the two gases in the mixture ?

  • Option 1)

    16 : 1

  • Option 2)

    2 : 1

  • Option 3)

    1 : 4

  • Option 4)

    4 : 1

 
  Partial Pressure of a gas in gaseous mixture - Partial Pressure = (Total Pressure of Mixture)  (mole fraction of gas)   -    suppose mass of     = then, mass of   =  Moles of   Moles of      Option 1) 16 : 1 This option is incorrect. Option 2) 2 : 1 This option is incorrect. Option 3) 1 : 4 This option is incorrect. Option 4) 4 : 1 This option is correct.
Medical
511 Views   |  

Three identical spherical shells, each of mass m and radius r are placed as shown in figure. Consider an axis XX' which is touching to two shells and passing through diameter of third shell.

Moment of inertia of the system consisting of these three spherical shells about XX' axis is :

 

  • Option 1)

    \frac{16}{5} mr^{2}

  • Option 2)

    4 mr^{2}

  • Option 3)

    \frac{11}{5} mr^{2}

  • Option 4)

    3 mr^{2}

 
As we learnt in  Moment of inertia for system of particle -   - wherein Applied when masses are placed discretely.     Option 1) Incorrect Option 2) Correct Option 3) Incorrect Option 4) Incorrect
Medical
100 Views   |  

Which one of the following is correct ?

  • Option 1)

    Lymph = Plasma + RBC + WBC

  • Option 2)

    Blood = Plasma + RBC + WBC + Platelets

  • Option 3)

    Plasma = Blood - Lymphocytes

  • Option 4)

    Serum = Blood + Fibrinogen

 
  Components of blood - Blood is a special connective tissue consisting of a fluid matrix, plasma, and formed elements.   -     Components of Blood - formed elements - wherein Erythrocytes, leucocytes and platelets are collectively called formed elements and they constitute nearly 45 per cent of the blood.       Option 1) Lymph = Plasma + RBC + WBC Incorrect option Option 2) Blood = Plasma...
Medical
90 Views   |  

Which of the following statements is not correct ?

  • Option 1)

    Oxyntic cells are present in the mucosa of stomach and secrete HCI.

  • Option 2)

    Acini are present in the pancreas and secrete carboxypeptidase

  • Option 3)

    Brunner's glands are present in the submucosa of stomach and secrete pepsinogen

  • Option 4)

    Goblet cells are present in the mucosa of intestine and secrete mucus

 
  Succus Entericus - This juice contains a variety of enzymes like disaccharidases (e.g., maltase), dipeptidases, lipases, nucleosidases, etc. - wherein The mucus alongwith the bicarbonates from the pancreas protects the intestinal mucosa from acid as well as provide an alkaline medium (pH 7.8) for enzymatic activities. Sub-mucosal glands (Brunner’s glands) also help in this    Brunner's gland...
Medical
120 Views   |  

When you hold your breath, which of the following gas changes in blood would first lead to the urge to breathe ?

  • Option 1)

    falling CO2 concentration

  • Option 2)

    rising CO2 and falling O2 concentration

  • Option 3)

    falling O2 concentration

  • Option 4)

    rising CO2 concentration

 
As learnt Partial pressure of CO2 as compared to O2 - As the solubility of CO2 is 20-25 times higher than that of O2, the amount of CO2 that can diffuse through the diffusion membrane per unit difference in partial pressure is much higher compared to that of O2. -    AND   Carbon dioxide (CO2) - Carbon dioxide (CO2) which is harmful is also released during the above catabolic...
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