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Medical
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The pair of electron in the given carbanion, CH3CH \equiv C\Theta, is present in which of the following orbitals?

  • Option 1)

    2p

  • Option 2)

    sp3

  • Option 3)

    sp2

  • Option 4)

    sp

 
As we learnt in  Carbanion - Those chemical species in which carbon bearing negative charge is called carbanion - wherein     This Carbon has two hybrid orbitals. One is involned in the formation of sigma bond and another occupy lone pair hence its symbolization is =sp     Option 1) 2p This is incorrect option Option 2) sp3 This is incorrect option Option 3) sp2 This is incorrect...
Medical
106 Views   |  

For the following reactions:

(a) CH3CH2CH2Br + KOH \rightarrow CH3CH = CH2 + KBr + H2O

(b) 

(c) 

Which of the following statements is correct?

  • Option 1)

    (a) and (b) are elimination reactions and (c) is addition reaction.

  • Option 2)

    (a) is elimination, (b) is substitution and (c) is addition reaction.

  • Option 3)

    (a) is elimination, (b) and (c) are substitution reactions.

  • Option 4)

    (a) is substitution, (b) and (c) are addition reactions.

 
This reaction is elimination reaction.   This reaction is nucleophilic substitution reaction. This reaction is an addition reaction. Option 1) (a) and (b) are elimination reactions and (c) is addition reaction. Incorrect Option 2) (a) is elimination, (b) is substitution and (c) is addition reaction. Correct Option 3) (a) is elimination, (b) and (c) are substitution...
Medical
145 Views   |  

The correct statement regarding the basicity of arylamines is :

  • Option 1)

    Arylamines are generally less basic than alkylamines because the nitrogen lone-pair electrons are delocalized by interaction with the aromatic ring \pi electron system.

  • Option 2)

    Arylamines are generally more basic than alkylamines because the nitrogen lone-pair electrons are delocalized by interaction with the aromatic ring \pi electron system.

  • Option 3)

    Arylamines are generally more basic than alkylamines because of aryl group.

  • Option 4)

    Arylamines are generally more basic than alkylamines, because the nitrogen atom in arylamines is sp-hybridized.

 
As we learnt in Amines - Amines are the derivatives of ammonia obtained by replacement of H atoms by any alkyl or aryl radicals.  -    Arylamines are less base than alkylamines because the nitrogen cone pair electrons are delocalised by interaction with aromic ring  electron system. Option 1) Arylamines are generally less basic than alkylamines because the nitrogen lone-pair electrons are...
Medical
1537 Views   |  

Equal moles of hydrogen and oxygen gases are placed in a container with a pin-hole through which both can escape. What fraction of the oxygen escapes in the time required for one-half of the hydrogen to escape?

  • Option 1)

    1/8

  • Option 2)

    1/4

  • Option 3)

    3/8

  • Option 4)

    1/2

 
As we learned in concept Graham’s law of diffusion -   where r is rate of diffusion of gas , M is molar mass. -    By  graham's law of diffusion of gas Option 1) 1/8 Option is correct Option 2) 1/4 Option is incorrect Option 3) 3/8 Option is incorrect Option 4) 1/2 Option is incorrect
Medical
216 Views   |  

Which of the following guards the opning of hepatopancreatic duct into the duodenum?

  • Option 1)

    Semilunar valve

  • Option 2)

    Ileocaecal valve

  • Option 3)

    Pyloric sphincter

  • Option 4)

    Sphincter of Oddi

 
  Hepato-pancreatic duct - The bile duct and the pancreatic duct open together into the duodenum as the common hepato-pancreatic duct - wherein It is guarded by a sphincter called the sphincter of Oddi.   Hepatopancreatic duct is guarded by sphincter of Oddi. Option 1) Semilunar valve This option is incorrect Option 2) Ileocaecal valve This option is incorrect Option 3) Pyloric sphincter This...
Medical
115 Views   |  

Reduction in pH of blood will:

  • Option 1)

    reduce the rate of heart beat.

  • Option 2)

    reduce the blood supply to the brain.

  • Option 3)

    decrease the affinity of hemoglobin with oxygen.

  • Option 4)

    release bicarbonate ions by the liver.

 
  Oxygen Dissociation Curve - A sigmoid curve is obtained when percentage saturation of haemoglobin with O2 is plotted against the . This curve is called the Oxygen dissociation curve and is highly useful in studying the effect of factors like , H+ concentration, etc., on binding of O2 with haemoglobin. - wherein    High concentration of H+ will reduce the pH, which will decrease the...
Medical
189 Views   |  

Name the chronic respiratory disorder caused mainly by cigarette smoking:

  • Option 1)

    Emphysema

  • Option 2)

    Asthma

  • Option 3)

    Respiratory acidosis

  • Option 4)

    Respiratory alkalosis

 
  DISORDERS OF RESPIRATORY SYSTEM - Emphysema - wherein Emphysema is a chronic disorder in which alveolar walls are damaged due to which respiratory surface is decreased. One of the major causes of this is cigarette smoking.       Option 1) Emphysema This option is correct. Option 2) Asthma This option is incorrect. Option 3) Respiratory acidosis This option is incorrect. Option...
Medical
89 Views   |  

Asthma may be attributed to:

  • Option 1)

    bacterial infection of the lungs

  • Option 2)

    allergic reaction of the mast cells in the lungs

  • Option 3)

    inflammation of the trachea

  • Option 4)

    accumulation of fluid in the lungs

 
As we learnt in  DISORDERS OF RESPIRATORY SYSTEM - Asthma - wherein Asthma is a difficulty in breathing causing wheezing due to inflammation of bronchi and bronchioles.        Asthma is one inflammation is bronchi and bronchioles due to a secretion of mast cells causes allergy. Option 1) bacterial infection of the lungs This option is incorrect Option 2) allergic reaction of the mast cells...
Medical
247 Views   |  

Photosensitive compound in human eye is made up of :

  • Option 1)

    Guanosine and Retinol

  • Option 2)

    Opsin and Retinal

  • Option 3)

    Opsin and Retinol

  • Option 4)

    Transducin and Retinene

 

OPSIN AND RETINOL

 

Medical
82 Views   |  

In the stomach, gastric acid is secreted by the :

  • Option 1)

    gastrin secreting cells

  • Option 2)

    parietal cells

  • Option 3)

    peptic cells

  • Option 4)

    acidic cells

 
As we learnt Layers of the Stomach - Mucosal epithelium - wherein Contains specialised cells that secrete chemicals necessary for digestive processes. These chemicals include gastric juice and the hormone gastrin   Gastric juice is secreted by the parietal cells.  Option 1) gastrin secreting cells incorrect Option 2) parietal cells correct Option 3) peptic cells incorrect Option 4) acidic...
Medical
123 Views   |  

Blood pressure in the pulmonary artery is:

  • Option 1)

    same as that in the aorta.

  • Option 2)

    more than that in the carotid.

  • Option 3)

    more than that in the pulmonary vein.

  • Option 4)

    less than that in the venae cavae.

 
As we learnt at concept pulmonary artery and the aorta - The openings of the right and the left ventricles into the pulmonary artery and the aorta respectively are provided with the semilunar valves. - wherein The valves in the heart allows the flow of blood only in one direction, i.e., from the atria to the ventricles and from the ventricles to the pulmonary artery or aorta. These valves...
Medical
205 Views   |  

Lack of relaxation between successive stimuli in sustained muscle contraction is known as:

  • Option 1)

    Spasm

  • Option 2)

    Fatigue

  • Option 3)

    Tetanus

  • Option 4)

    Tonus

 

Wild contraction- spasm

Slight contraction - tonus 

Sustained contraction - tetany or tetanus

Medical
95 Views   |  

A car is negotiating a curved road of radius R. The road is banked at an angle \theta. The coefficient of friction between the types of the car and the road is \mus. The maximum safe velocity on this road is:

  • Option 1)

    \sqrt{gR^{2}\frac{\mu_{s}+tan\theta}{1-\mu_{2} tan\theta}}

  • Option 2)

    \sqrt {\text{gR}\frac{{\mu _\text{s} + \tan \theta }} {{1 - \mu _\text{s} \tan \theta }}}

  • Option 3)

    \sqrt {\frac{\text{g}} {\text{R}}\frac{{\mu _\text{s} + \tan \theta }} {{1 - \mu _\text{s} \tan \theta }}}

  • Option 4)

    \sqrt {\frac{\text{g}} {{\text{R}^\text{2} }}\frac{{\mu _\text{s} + \tan \theta }} {{1 - \mu _\text{s} \tan \theta }}}

 
As we learnt in  If friction is also present in banking of road -  angle of banking coefficient of friction V = velocity - wherein Maximum speed on a banked frictional road     Option 1) Incorrect Option 2) Correct Option 3) Incorrect Option 4) Incorrect
Medical
554 Views   |  

Lithium has a bcc structure. Its density is 530 kg m-3 and its atomic mass is 6.94g mol-1. Calculate the edge lenth of a unit cell of Lihium metal. (NA = 6.02 x 1023 mol-1)

  • Option 1)

    154 pm

  • Option 2)

    352 pm

  • Option 3)

    527 pm

  • Option 4)

    264 pm

 
As we learnt in  Density of cubic unit cell -   - wherein Where, d = density of crystal z = no. of effective constituent particles in one unit cell M = molecular weight a = edge length of unit cell No = 6.022*1023   Density of cubic unit cell Option 1) 154 pm Option is incorrect Option 2) 352 pm Option is correct Option 3) 527 pm Option is incorrect Option 4) 264 pm Option is incorrect
Medical
291 Views   |  

A gas is compressed is isothermally to half its initial volume. The same gas is compressed separately through and adiabatic process until its volume is again reduced to half. Then:

  • Option 1)

    Compressing the gas isothermally will require more work to be done.

  • Option 2)

    Compressing the gas through adiabatic process will require more work to be done.

  • Option 3)

    Compressing the gas isothermally of adiabatically will require the same amount or work.

  • Option 4)

    Which of the case (wheather compression through isothermal or through adiabatic process) requires more work will depend upon the atomicty of the gas.

 
As we learnt in Comparision between isothermal and adiabatic process in compression - - wherein       Consider the P-V indicator diagram shown below.  ia  Isothermal process ib  Adibatic process Since slope of adiabatic process is greater than slope of isothermal process. Work done under adiabatic process is greater than work done under isothermal process as area under ib is greater than...
Medical
193 Views   |  

The product formed by the reaction of an aldehyde with a primary amine is:

  • Option 1)

    Schiff base

  • Option 2)

    Ketone

  • Option 3)

    Carboxylic acid

  • Option 4)

    Aromatic acid

 
As we learnt in Addition of ammonia and its derivatives with aldehydes and ketones - Product formation is favoured due to rapid dehydration of the intermediate to form  > C = NG - wherein       Option 1) Schiff base Correct Option 2) Ketone Incorrect Option 3) Carboxylic acid Incorrect Option 4) Aromatic acid Incorrect
Medical
335 Views   |  

A astronomical telescope has objective and eyepiece of focal lengths 40 cm and 4 cm respectively. To view an object 200 cm away from the objective, the lenses must be separated by a distance :

  • Option 1)

    67.3 cm

  • Option 2)

    46.0 cm

  • Option 3)

    50.0 cm

  • Option 4)

    54.0 cm

 
As we discussed in For astronomical telescope Object distance for objective lens For 1st image : or Since image will form at focal point of eyepiece, hence distance of this image from eyepiece = 4 cm Hence distance between objective and eyepiece = (50+4) cm                                                                                 = 54 cm Option 1) 67.3 cm This option is...
Medical
103 Views   |  

An inductor 20 mH, a capacitor 50 \mu F and a resistor 40 \Omega are connected in series across a source of emf V = 10 sin 340 t. The power loss in A.C circuit :

  • Option 1)

    0.51 W

  • Option 2)

    0.67 W

  • Option 3)

    0.76 W

  • Option 4)

    0.89 W

 
  Impedence - -     Average power (True power) - -    and   Power factor -   - wherein resistance impedence     Peak Current -   Power loss in A.C circuit = P = Vrms I rms      Option 1) 0.51 W Correct option Option 2) 0.67 W incorrect option Option 3) 0.76 W incorrect option Option 4) 0.89 W incorrect option
Medical
424 Views   |  

A long solenoid has 1000 turns. When a current of 4A flows through it, the magnetic flux linked with each turn of the solenoid is 4 x 10-3 Wb. The self-inductance of the solenoid is:

  • Option 1)

    4 H

  • Option 2)

    3 H

  • Option 3)

    2 H

  • Option 4)

    1 H

 
As discussed in Co efficient of self induction -   - wherein Number of flux linkage with coil.     Total flux linked with the solenoid,  Option 1) 4 H This option is incorrect. Option 2) 3 H This option is incorrect. Option 3) 2 H This option is incorrect. Option 4) 1 H This option is correct.
Medical
504 Views   |  

Two electrons occupying the same orbital are distinguished by :

  • Option 1)

    Principle quantum number

  • Option 2)

    Magnetic quantum number

  • Option 3)

    Azimutual quantum number

  • Option 4)

    Spin qauntum number

 
  Spin Quantum Number (s) - It has two values +1/2 and -1/2 -    For the two electrons occupying the same orbital value of  n, l amd m are same but is different  i.e. Option 1) Principle quantum number This is incorrect option Option 2) Magnetic quantum number This is incorrect option Option 3) Azimutual quantum number This is incorrect option Option 4) Spin qauntum number This is correct option
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