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(A) Cathode is Lead dioxide (PbO₂) and anode is Lead (Pb)

Correct option (C) both of these (A and B)   

Explanation:

Grignard’s reagent reacts with primary or secondary amines to give alkanes but fail to react with tertiary amines due to lack of hydrogen on nitrogen.

R-MgX + R-NH₂ → R-H + Mg(NHR)

The reaction between ethanol and Grignard is shown below:

CH₃CH₂OH + R’MgX → CH₃CH₂O-(MgX)⁺ + R’-H

Correct option (a) 0.1 M BaCl₂  

Explanation:

Lowering of vapour pressure is directly proportional to the van't Hoff faotor 

(i). For BaCl₂,i = 3 (maximum)

Thus, BaCl₂ has highest value relative lowering of vapour pressure.

Correct option (A) 3-methyl-2-butanone  

Explanation:

The IUPAC name of the compound CH₃–CH(CH₃)–CO–CH₃ is 3-methyl-2-butanone. 

Correct option (C) 12  

Explanation:

HCP means "hexagonal close packing" structure. 

In hcp, the unit cell is hexagonal and coordination number is 12. 

Correct Option: (a) 0

Explanation:

Given,

2x + y - z = 7 ...(i)

x - 3y + 2z = 1

and x + 4y - 3z = 5 ...(iii)

Multiplying (i) by 2 and then adding (i) and (ii), we get

5x - y = 15 ...(iv)

Multiplying (i) by 3 and then subtracting (iii) from (i), we get

5x - y = 16 ...(v)

Eqs. (iv) and (v) shows that they are parallel and so solution does not exist.

Correct option: (b) (-10,15)

Explanation:

Let the point (x₁, y₁) be on the line 4x + 3y = 5.

∴  4x₁ + 3y₁ = 5 ...(i)

Distance of point (x₁, y₁) from (1, 2) is (x₁ –1)² + (y₁ - 2)²

Distance of point (x₁, y₁) from (3, 4) is (x₁ - 3)³ + (y₁ - 4)²

It is given, point (x₁, y₁) is equidistant from (1, 2) and (3, 4)

(x₁ –1)² + (y₁ - 2)² = (x₁ - 3)³ + (y₁ - 4)²

=> x² + 1 - 2x₁ + y² + 4 - 4y₁ = x² + 9 - 6x₁ + y₁² + 16 - 8y₁

=> 4x₁ + 4y₁ = 20

=> x₁ + y₁ = 5 ...(ii)

From Eqs. (i) and (ii), we get

y₁ =15 and x₁ = -10

Correct option  (B)  |α| < 5/3

Explanation:

|α| < 5/3  as the line y = x intersect lines |2x + 5| = 5 at points (5/3,5/3) & (- 5/3, - 5/3)

Correct option (D) It is a strong oxidant and oxidizes other components of atmosphere   

Explanation:

Sulphur dioxide (SO₂) is considered as air pollutant because it readily undergoes oxidation in the atmosphere to form Sulphur trioxide (SO₃). Sulphur trioxide gets convert into H₂SO₄ in the presence of moisture, which comes down in the form acid rain.

Correct option (C) associate

Explanation:

At CMC they associate

Correct option (A ) 0.6 m /s 

Explanation:

By momentum conservation

(10 x 10^-3 )1000= (10 x10^-3 ) x 400 +10v

⇒ v 0.6m /s

Correct option (A) nitroglycerine, guncotton and vaseline   

Explanation:

Cordite is a mixture of nitroglycerine, guncotton and Vaseline used in ammunition.

Correct option (B)

Explanation:

2⁰ Carbocation will be more stable than 1⁰

Substituted carbocation will more stable than simple

Correct option (A) Nickel   

Explanation:

Nickel is the material that requires the least value of magnetic field strength to magnetize.

 Sulphur is a lyophobic colloid.

Correct option (b) high-high   

Explanation:

Permanent magnet has high retentivity and high coercivity.

Correct option (a) maximum (B)  

Explanation:

Mutual inductance depends on their degree of flux linkage. In (B) and (C) the flux linkage is less than A. 

So, the mutual inductance of (A) will be maximum.

Correct option (c) constant in magnitude as well as direction  

Explanation:

The acceleration of the point A is will be constant in magnitude as well as direction

(D) (ΔS _system + ΔS _surrounding ) >0

Correct option: (a) 3

Explanation: 

Given,

Equation of Circle: x² + y² - 6x + 2y = 0

x² + y² - 6x + 2y = 0

=> (x - 3)² + (y + 1)² = 10

From the above equation,

Centre: (3, -1)

Radius: √10

Since centre lies on the diameter so,

(3, -1) will lie on the diameter x + 2ky + 3 = 0

=> 3 - 2k + 3 = 0

=> 6 - 2k =0

=> k = 3

Correct option (C)   √3/2

Explanation:

Given L : sin a + sin b = 1/√2  & M : cos a + cos b =  √6/2,

So L² + M²  implies cos (a - b) = 0

while L M (using cos (a - b) = 0)

gives sin (a + b) =  √3/2

Correct option (D) Friedal-crafts Acylation followed by clemmensen reduction   

Explanation:

Friedel-Crafts Acylation followed by clemmensen reduction of ketone will give n-propyl benzene. Clemmensen reduction is a chemical reaction described as a reduction of ketones (or aldehydes) to alkanes using zinc amalgam and hydrochloric acid.

Correct option (b) 246 Hz  

Explanation:

Possible frequencies of P are: (250 ± 4) Hz i.e. 246 Hz, 254 Hz 

When the prong of P is filled, its frequeney becomes greater than the original frequeney of P. 

Also the frequency of P when the prong is filled reduces to 2 beats s^-1 . 

New possible frequencies of P are: (250 ± 2) Hz i.e. 248 Hz, 252 Hz 

Since the new frequency increases from the original frequency. 

So, the new frequency will be 246 Hz.

Correct option (a) Weakest intermolecular forces  

Explanation:

Vulcanised rubber is highly elastic, so weakest intermolecular forces are present in it.

Correct option (B) n = 4, l= 0,  m = 0, s = +1/2

Explanation:

For option (A ) electron is in 3d For option 

(B) electron is in 4s For option 

(C) electron is in 4p For option 

(D) electron is in 5s

According to A ufbau principle 4s<3d<4p<5s. Hence Answer will be n=4,l=0, m=0,s= +1/2

Correct option (a) High temperature. low pressure   

Explanation:

At higher temperature and low pressure real gas acts as an ideal gas.

Correct option (A ) experiences a force directed along the radial direction only.  

Explanation:

Circular motion is a special case in gravitational field. T here may be straight line,elliptical paths, but force will be always directed toward the centre of the sphere.

Correct option (C) (R, S) - 2 - 3 - dibromobutane  

Explanation:

The addition of Br₂ to (E) – but – 2 – ene gives (R, S) - 2 - 3 – dibromobutane.

Correct option (C) 9 σ + 9 π
Explanation:

We know that, 

In 1 single bond = 1 σ bond, 

In 1 double bond = 1 σ bond + 1 π bond 

In 1 triple bond + 1 σ bond + 2 π bonds

The given compound has 4 single bonds which is equal to 4 σ bond. 

Also, the given compound has 1 double bond which is equal to 1 σ bond and 1 π bond. 

In the given compound there are 4 triple bonds which mean 4 σ bond and 8 π bond. Therefore, the given compound has 9 σ and 9 π bonds.

Correct option (c) Orlon

Explanation:

Orlon is an addition polymer as its molecular mass is integral rnultiple of molecular mass of its monomer.

Correct option (a) Li > Na > K > Cs   

Explanation:

In a group atomic size inereases as we move from top to bottom. So, the amount of energy required for ejection of an electron from atom decreases i.e. ionisation energy decreases. So, the decreasing order of ionisation energy in group 1A is as follows: 

Li > Na > K > Cs

Correct option (D) 200 J   

Explanation:

According to first law of thermodynamics, 

∆Q − ∆W = ∆U 

For adiabatic process, ∆Q = 0

∆W = −∆U 

Therefore, the work done during adiabatic process is negative of the change in internal energy. 

Thus, the work done by the gas during the process will be equal to 200 J.

Correct option (A) Only –I effect

Explanation:

Due to SIR effect –NO₂ group goes out of plane of the paper (-I)

Correct option (b) C₆H₅CHO   

Explanation:

C₆H₅CHO has no H and α-carbon. 

Thus, no aldol condensation reaction is given by C₆H₅CHO

Correct option (C) C₃H₆ + HBr  

Explanation:

Markovnikoc’s rule states that when a protonic acid (HX, where X can be any group with a higher electronegativity than hydrogen) is added to an asymmetric alkene (The groups on the two sides of the double bond are not the same), the hyfrogen atom is added to the carbon with the greatest number of hydrogen atoms while the X is added to the carbon with the least number of hydrogen atoms.

For example

CH₃CH=CH₂+HBr → CH₃CHBrCH₃

Correct option  (c)CH₂=CHCI 

Explanation:

Vinyl chloride is least reactive for nucleophilic substitution reaction due to resonance stabilisation of C —Cl bond.

Correct option (D)  

Explanation:

The compound given in the last option will be most reactive for electrophilic addition reaction.

Correct option (C) 55 km/hr   

Explanation:

The relative velocity of man with the respect to train is 80 – 10 = 70 km/hr towards Hubli 

The relative velocity of plate with respect to man is 70 – 20 = 50 km/hr towards Hubli 

Therefore, velocity of spider approaching Hubli is 50 + 5 = 55 km/hr.

Correct option (B) Fractional distillation  

Explanation:

Fractional distillation is used in refining of Petroleum,

Correct option (B) B < S < P < F

Explanation:

I.P. in period increases ↑ left to right. 

I.P. in group up to down↓ decreases

Correct option: (b) 39²

Explanation:

If in two sets A and B n elements are common, then the number of elements common to each of the sets A x B and B x A are n².

So, the number of elements common to each set is 39 x 39 = (39)².

Correct option (A ) 84m²  

Explanation:

Result should have only two significant numbers (same as 12m).

Correct option: (C) 2

Correct option: (b)

Correct option: (C) ±1

Correct option (C) Ag   

Explanation:

The first transition series contain elements from atomic number 21 to 30. 

But the atomic number of Silver (Ag) is 47. 

Therefore, Ag is not in first transition series.

Correct option (C) 2, 4 dinitrophenylhydrazine  

Explanation:

2, 4 dinitrophenylhydrazine is capable of giving test both of Aldehyde and Ketones. As Aldehydes & Ketones both contain the carbonyl group, >C=O, but in aldehydes the carbonyl group is attached to one or two hydrogen atoms whereas in ketones it is linked to two alkyl or aryl groups. 

Correct option (C) 2KBr + I₂ → 2KI + Br₂  

Explanation:

According to the reactivity series, Iodine is less reactive than Potassium. 

Therefore, Iodine cannot displace Potassium from KBr.

So, 2KBr + I₂ → 2KI + Br₂ will not occur. 

Correct option (d) electron excitation   

Explanation:

In helium-neon laser population inversion is produced by electron excitation.

Correct option (d) electron excitation   

Explanation:

In helium-neon laser population inversion is produced by electron excitation.