24633031
Description
Flashcards by Pranjal Pratosh, updated more than 1 year ago
|
Created by Pranjal Pratosh
almost 4 years ago
|
|
| Question | Answer |
| Which one of the following gives ketone on oxidation? | Oxidation of secondary alcohols gives ketones. |
| For a particle to be a colloid, its size must be... | 1nm - 100nm |
| What is the Kinetic energy of two moles of N at 27C? | KE of n moles of gas, (N2) = (3/2)nRT |
| heat treatment alters properties of steel due to? | Change in the lattice structure... |
| Which of the transition element do not form amalgams? | Iron |
| Which is not an electrophile? | NH3 is not an electrophile. Explanation: Electrophile are those ions or compounds which are either positively charged or have vacant orbitals in it so that they can attract an electron towards it. Ammonia consists of Nitrogen which does not have D orbital. On the other hand it has a lone pair of electron which repels when other electron approach towards it. As a result ammonia can never act as an electrophile. This is because there is repulsion between the lone pair of electron and other approaching electrons. |
| Total No. of spectral lines obtained in the visible region during the jump of e- from the fourth excited state of the hydrogen atom? | Visible lines ⇒ Balmer series (5→2,4→2,3→2). So 3 lines. |
| 2C(s) + O2(g) -> CO(g). In the Ellingham diagram, the slope is downwards, this means... | ▲G becomes more and more negative as T increases. |
| The equation of normal to x=4secφ, y=3tanφ at φ =n/3 | Slope = -dx/dy y-3tanφ = -4/3 sinφ (x-4secφ) ⇒ 2x+√3 y=25 |
| The equation of line parallel to x+4/-3 = y-4/2=z+1/3 and passing through (3,2,-6) | D.r.'s of a the given line are -3,2,3 x+6/-3 = y-4/2=z-3/3 |
| If z is a complex root of z²+z+1 then inverse of |1 z| |0 z²| | A^-1=Adj A/|A| inverse = |1 -1/z| |0 1/z²| |
| Sum of 1+2/3+3/3²+4/3³+... | S = 1+2/3+3/3²+4/3³+... S/3 = 1/3+2/3²+3/3³+... S-S/3 = 1+1/3+1/3²+1/3³+... 2S/3 = 1/1-1/3 2S/3 = 3/2 S = 9/4 |
| xi+3j-k, i+2j+3k and 3i+2k are coplanar. Find x | If a ,b ,c are coplanar, then their scalar triple product should be zero. [a b c ]=0 That implies, (a ×b ).c =0 By cyclic rotation, (b ×c ).a =0 b ×c = 4i+7j-6k (4i+7j-6k).(xi+3j-k)=0 x = -27/4 |
| Area enclosed by y=lnx, y=0, and x=e is.. | ▲=int_1^e lnx.dx = [x(lnx-1)]_1^e = 1 |
| lim (x*2^x-x)/(1-cos2x) as x->0 | 0/0 form [Find the zero culprit and eliminate it!] [Separate the zero culprit by rationalization and destroy it!] Use L'Hospitals rule twice. = (log2)/2 |
| In a capillary tube, the water rises to a height 1.2mm. The height of water in a tube of half the radius as that of the first one. | pgh = 2T/R h is proportional to 1/R h1/h2 = R1/R2 h2 = 2h1 |
| The value of tan^-1(1/2)+tan^-1(1/5)+tan^-1(1/9) | 45 or π/4 |
| Suppose that each of n men at a party throws his hat into the center of the room. The hats are mixed up and then each man randomly selects a hat. What is the expected number of men who select their own hat? | 1 |
| If the slope of one of the lines represented by x²-5xy+4y²=0 is 1/4, then the slope of the other line is... | ax²+2hxy+by²=0 φ=tan^-1((2√h²-ab)/(a+b)) m1+m2 = -2h/b, m1m2 = a/b 1/4 + m2= 5/4 |
| Toluene is more reactive than benzene due to.. | Inductive effect, it adds electron density to the ring. |
| Two resistances R1 and R2 are in series, while R3 and R4 are in parallel. If R1/R2=1/4, R3/R4=1/3 and Rs=Rp, then. | R1+R2=R3R4/R3+R4 R1/R3=3/20 |
| A flywheel of uniform mass 72 kg and radius 50cm. when it is rotating with 70 rpm, its KE is.. | Kinetic energy = 1/2 mv^2 Kinetic energy = 1/2 × m × (r × 2πf)^2 r = 50 cm = 0.5 m f = 70 rpm = 70/60 Hz Kinetic energy = 483.61 J |
| A line making a acute angle a with +ve x-axis passes through P(5,6) to meet line at x=6 at Q and y=9 at R, Then QR is given by... | 2(3cos a-sin a)/(sin2a) |
| if w is a non real cube root of unity what is w^40+1/w^40 | w^(n) n=40 ans. w |
| A bar magnet when placed at an angle of 30 to the direction of the magnetic field induction of 4 x 10^-4 T, experiences a moment of couple 24x10^-6 Nm. The magnetic moment of bar magnet is | τ=MBsinθ M=(24x10^-6)/(4 x 10^-4)*0.5 M=12x10^-2 Am² |
| Diffraction effects are observed in day to day life with sound waves rather than light waves, this is because... | wavelength of sound waves is much greater than that of light waves. |
| The Ellingham diagram of Al2O3 formation is lower than that of Cr2O3 formation | [Lower the line of formation in Ellingham diagram, the greater is the stability of its oxide] Aluminum can reduce Cr2O3 to Cr |
| The effective atomic number of the central atom in the the complex [Fe(CO)3] | EAN= Z – x + 2nL Z= Atomic number of the metal in the complex x = Oxidation state of the metal in complex n= Number of the ligands L = Number of co-ordinate bonds formed by ligand (monodentate=1, bi=2, tri=3) EAN = 26-0+2(3)(1) = 32 |
| If the straight line 2x+3y+6=0 is a tangent to the parabola y²=4ax, then the value of a is.. | y=mx + a/m m=-2/3 a/m = -2 a=4/3 |
| The escape velocity from the earth’s surface is 11 km/sec. A certain planet has a radius twice that of the earth but its mean density is the same as that of the earth. The value of the escape velocity from this planet would be | Ve=√2GM/R =√(2GM)p(4π/3)*R³ =√(8π/3)GpR² Vp/Ve = Rp/Re Vp = 22km/sec |
| If f(x)=ln(ln(x)), then f'(e)=.. | f'(x)=1/(lnx)² f'(e)=1/ 1² =1 |
| The product of the perpendiculars from any point on 4x²-5y²=20 to its asymptotes is | x²/a²+y²/b² = 1 d1d2= (a²b²)/(a²+b²) =20/9 |
| Which of the following produce benzene from phenol? | vapors of phenol are passed over heated zinc dust |
| If the two root of the eq, x³-px²+qx+r²=0, are equal in magnitude but opposite in sign, then | r²=pq p, q, r are in G.P |
Want to create your own Flashcards for free with GoConqr? Learn more.