This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 95251. |
Element with electronic configuration as `[Ar]^(18)3d^(5)4s^(2)` is placed in `:`A. `1^(st)`group, `s-` blockB. `2^(nd) ` group, `s-` blockC. `5^(th) ` group, `d-` blockD. `7^(th) ` group, `d-` block |
|
Answer» Correct Answer - 4 Last electrons enters in `d-` orbital. So it belong to `d-` block. For `d-` block elements the group number is equal to the number of valence electrons `+` number of electrons in `(n-1)d` subshell `i.e., 2+5=7^(th)` group. |
|
| 95252. |
A metal has electronic configuration `[Ar]^(18)3d^7 4s^2`.On the basis of this electronic configuration find out the group number. |
|
Answer» Correct Answer - 9 Last electron enter in d-subshell so it belongs to d-block elements. For d-block elements group number =no of electrons in (n-1)d subshell+number of electrons in valence shell (i.e. ns) =7+2=9 |
|
| 95253. |
A short circuited stub is shunt connected to a transmission line as shown in figure. If z0 = 50Ω, the admittance Y seen at the junction of the stub and transmission line is(a) (0.01 – j 0.02) mho (b) (0.02 – j 0.01) mho (c) (0.04 + j 0.02) mho (d) (0.02 + j 0) mho |
|
Answer» Correct option (a) (0.01 – j 0.02) mho Explanation: For both Transmission line and stub, z0 = 50Ω For λ/2 line input impedance zil = zL zil = zL = 100Ω yil = 0.01mho For short circuited stub input impedance zi2 = jz0tan(βl) = jz0tan(2πλ/λ8) = jz0tan(π/4) = jz0 = j50 Yi2 = 1/j50 = - j 0.02 Y = Yil + Yi2 = (0.01 - j 0.02) mho |
|
| 95254. |
A transmission line of characteristic impedance 50Ω is terminated by a 50Ω load. When excited by a sinusoidal voltage source at 10 GHz, the phase difference between two points spaced 2 mm apart on the line is found to be π/4 radians. The phase velocity of the wave along the line is (a) 0.8 × 108m/s (b) 1.2 × 108m/s (c) 1.6 × 108 m/s (d) 3 × 108 m/s |
|
Answer» Correct option (c) 1.6 × 108 m/s Explanation: Phase difference βl = 2π/λ path difference π/4 = 2π/λ(2 x 10-3) λ = 8 x 2 x 10-3 = 16 x 10-3m Given, f = 10GHz The phase velocity of the wave: Vp = fλ =10 x 109 x 16 x 10-3 = 160 x 106m/sec = 1.6 x 108m/sec |
|
| 95255. |
A charge 'q' move in region where electric field 'E' and magnetic field 'B' both exist, then force on it is :- |
|
Answer» Correct answer is (C) |
|
| 95256. |
Coefficient of friction formulae |
|
Answer» coefficient of friction, ratio of the frictional force resisting the motion of two surfaces in contact to the normal force pressing the two surfaces together. It is usually symbolized by the Greek letter mu (μ). Mathematically, μ = F/N, where F is the frictional force and N is the normal force. |
|
| 95257. |
An instrumentation amplifier has a high a. Output impedance b. Power gain c. CMRR d. Supply voltage |
|
Answer» The correct answer is: (c) CMRR |
|
| 95258. |
Compared to the ac resistance of the emitter diode, the feedback resistance of a swamped amplifier should be a. Small b. Equal c. Large d. Zero |
|
Answer» The correct answer is: (c) Large |
|
| 95259. |
The emitter of a swamped amplifier a. Is grounded b. Has no de voltage c. Has an ac voltage d. Has no ac voltage |
|
Answer» (c) Has an ac voltage |
|
| 95260. |
Compared to a CE stage, a swamped amplifier has an input impedance that is a. Smaller b. Equal c. Larger d. Zero |
|
Answer» The correct answer is: (c) Larger |
|
| 95261. |
In a swamped amplifier, the effects of the emitter diode become a. Important to voltage gain b. Critical to input impedance c. Significant to the analysis d. Unimportant |
|
Answer» (d) Unimportant |
|
| 95262. |
Limits of poissons ratio |
|
Answer» Generally, the value of Poisson's ratio ranges from -1 to +0.5 . |
|
| 95263. |
Why HF acid is stored in wax coated glass bottle ? |
|
Answer» This is because HF does not attack wax but reacts with glass.It dissolves SiO2 present in glass forming hydrofluorosilicic acid. SiO2 + 6HF → H2SiF6 + 2H2O [Hint : HF is corrosive, hence HF attacks glass surface.] |
|
| 95264. |
Bond dissociation enthalpy of F2 is less than that of Cl2. Explain why ? |
|
Answer» [Hint : F2 is having higher electron-electron repulsion due to its smaller size, as |
|
| 95265. |
The ionic charges of manganate and permanganate ion are respectivelyA. `-2,-2`B. `-1,-2`C. `-2,-1`D. `-1,-1` |
|
Answer» Correct Answer - C Chemical formula for manganate and permanganate ion respectively are `Mn_(4)^(2-)` and `mnO_(4)^(-)`. Thus, the ionic charge of manganate and permangante ion are respectively -2 and -1. |
|
| 95266. |
(i). State Kohlraush law of independent migration of ions (ii). Write Nernst’s equation for the following cell :Zn (s) I Zn2+ (aq) II Cu2+(aq) I Cu (s) (iii).Calculate ∆G0 for the following reaction:Mg (s) + Cu2+(aq) → Mg2+(aq) + Cu (s)[Given E0cell = +2.71 V, 1F = 96500 C/Mol] |
|
Answer» (i) Kohlrausch's law of independent migration of ions states that the limiting molar conductivity of an electrolyte can be represented as the sum individual contributions of its cations & anions. (ii) Ecell = E0cell - \(\frac{0.0591}{2}log\frac{[zn^{2+}]}{[cu^{2+}]}\) (iii) ∆G = -nFE0 = - 2× 96500 × 2.71 = 523030 J |
|
| 95267. |
Discuss the nature of bonding in the following coordination entities on the basis of valence bond theory: (i). `[Fe(CN)_6]^(4-)` (ii). `[FeF_6]^(3-)` (iii). `[Co(C_2O_4)_3]^(3-)` (iv). `[CoF_6]^(3-)` |
|
Answer» (i). `[Fe(CN)_6]^(4-)` `-d^(2)sp^(3)` octahedral, diamagnetic (ii). `[FeF_6]^(3-)` `-sp^(3)d^(2)`, octahedral, paramagnetic (iii). `[Co(C_2O_4)_3]^(3-)` `-d^(2)sp^(3)` octahedral diamagnetic `(C_2O_4^(2-)` is a stong ligand) (iv). `[CoF_6]^(3-)` `-sp^(3)d^(2)`, octahedral, paramagnetic. |
|
| 95268. |
Assertion: A solution of `[Ni(H_(2)O)_(6)]^(2+)` is green but a solution of `[Ni(CN)_(4)]^(2-)` is colourless Reason: `[Ni(CN)_(4)]^(2-)` is square planar complex . |
|
Answer» In `[Ni(H_2O)_6]^(2+)`, Ni is in `+2` state with the configuration `3d^(8)`, i.e., it has two unpaired electrons which do not pair up in the presence of the weak `H_2O` ligand. Hence, it is coloured. The d-d transition, absorbs red light and the complementary light emitted is green. In case of `[Ni(CN)_4]^(2-)`, Ni is again in `+2` state with the configuration `3d^(8)` but in presence of the strong `CN^(ɵ)` ligand, the two unpaired electrons in the `3d` orbitals pair up. Thus, there is no unpaired electron present. Hence, it is colourless. |
|
| 95269. |
What are `t_(2g)` and `e_(g)` orbitals? |
| Answer» In a free stransition metal ion, the five d-orbita,ls are degenerate. When it forms a complex, the degeneracy is split. Three d-orbitals having lower energy are called `t_(2g)` orbitals and the remaining two d-orbitals of higher energy are called `e_(g)` orbitals. | |
| 95270. |
(i). What is crystal field splitting energy? How does the magnitude of ∆0 decide the actual configuration of d-orbital in a coordination entity? (ii). Co (II) is very stable in aqueous solutions but get easily oxidised in presence of strong ligands. Why? |
|
Answer» (i) When ligands approach a transition metal ion, the d-orbitals split into two sets, one with lower energy and the other with higher energy. The difference of energy between the two sets of orbitals is called crystal field splitting energy (△0) for octahedral field. If △0<P (pairing energy) the 4th electron enters one of the egeg orbitals giving the configuration t32geg1 Thus forming high spin complexes. Such ligands for which △0<P are called weak field ligands. If △0<P the 4th electron pairs up in one of the t2g orbitals giving the configuration t2g4eg0 thereby forming low spin complexes. Such ligands for which △0>P are called strong field ligands. (ii) Water is weak ligand and cannot paired up the electrons, but strong ligand have a tendency to pair up the electrons, so CO2+ is stable in aqueous solution but in the presence of strong ligands it is easily oxidised. |
|
| 95271. |
From where dose the electrical energy come in a generator ? |
|
Answer» A generator is a device that transforms mechanical energy into electrical energy. A generator do not create electricity instead it uses the mechanical supplied to it to force the movement of electric charge present in the wire of its windings though an external electric circuit. This Flow of electrons constitutes the output electric current supplied by the generator. |
|
| 95272. |
If \(f(n) =\begin{cases}\frac{x^2 - 4}{x - 2},\,x \neq 2 \\k,x=2\end{cases}\) is continuous at x = 2, then k =f(n) = {(x2 - 4)/(x - 2), x ≠ 2, k, x = 2 is continuous at x = 2, then k =(a) 2 (b) 4 (c) 6 (d) 3 |
|
Answer» Correct answer is (b) 4 |
|
| 95273. |
the power house of the cell is |
|
Answer» The power house of the cell is Mitochondria. |
|
| 95274. |
what is the general formula for monosaccharides |
|
Answer» Monosaccharides are the simplest carbohydrates; they conform to the general chemical formula (CH2O)x and are termed simple sugars. |
|
| 95275. |
the general formula of monosaccharides is |
Answer»
|
|
| 95276. |
`0.01` mol of a gaseous compound `C_(2)H_(2)O_(x)` was treated with `224 mL` of `O_(2)` at `STP`. After combustion the total volume of the gases is `560 mL` at `STP`. On treatment with `KOH` solution the volume decreases to `112 mL`. The volue of `x` is:A. `4`B. `2`C. `3`D. None of these |
|
Answer» Correct Answer - A vol.of `CO_(2) +` vol. of remaining oxygen `= 560 ml`. or vol. of remaining oxygen `= 112 mL` `C_(2)H_(2)O_(x)(g) + ((5-x)/(2))O_(2)(g)overset(Delta)rarr2CO_(2)(g) + H_(2)O(l)` `{:(224 mL,224 mL,0,-),(0,112 mL,448 mL,-):}` for used mole of a`O_(2)`: `((5-x)/(2)) xx 0.1 = (0.01)/(2)` or `x = 4` |
|
| 95277. |
`M(OH)_(X)` has `K_(SP) 4xx10^(-12)` and solubility `10^(-4) M`. The value of `x` is:A. `1`B. `2`C. `3`D. `4` |
|
Answer» Correct Answer - B `{:(M(OH)_(x)hArr,M^(+x)+,xOH^(-)),(,s,xs):}` `K_(sp) = S.(XS)^(x) = X^(x).S^((x+1)) = 4 xx 10^(-12)` given `() S = 10^(-4)` `:. x = 2` |
|
| 95278. |
If the vectors transmit the infection mechanically they are called a. Biological vectors b. Mechanical vectors c. Biological reservoir d. Both a and c |
|
Answer» b. Mechanical vectors |
|
| 95279. |
Small pox vaccine was first discovered by a. Robert Koch b. Louis Pasteur c. Lister d. Edward Jenner |
|
Answer» Small pox vaccine was first discovered by Edward Jenner. |
|
| 95280. |
Which is the following enzyme acts as a spreading factor? a. Hyaluronidase b. Coagulase c. Catalase d. DNase |
|
Answer» a. Hyaluronidase |
|
| 95281. |
B.anthracis was isolated by a. Louis Pasteur b. Robert Koch c. Antonyvon Leewenhok d. None of these |
|
Answer» b. Robert Koch |
|
| 95282. |
The principle light- trapping pigment molecule in plants, Algae, and cyanobacteria is a. Chlorophyll a b. Chlorophyll b c. Porphyrin d. Rhodapsin |
|
Answer» a. Chlorophyll a |
|
| 95283. |
Reverse isolation would be appropriate for a. a patient with tuberculosis b. a patient who has had minor surgery c. a patient with glaucoma d. a patient with leukemia |
|
Answer» a. a patient with tuberculosis |
|
| 95284. |
The capacity of a given strain of microbial species to produce disease is known as a. Pathogen b. Virulence c. Infection d. None of these |
|
Answer» The capacity of a given strain of microbial species to produce disease is known as Virulence. |
|
| 95285. |
Disease that effects many people at different countries is termed as a. Sporadic b. Pandemic c. Epidemic d. Endemic |
|
Answer» Disease that effects many people at different countries is termed as Sporadic. |
|
| 95286. |
The ability of a pathogen to spread in this host tissues after establishing the infection is known as a. Adhesion b. Invasiveness c. Toxigenicity d. None of these |
|
Answer» b. Invasiveness |
|
| 95287. |
Tuberculosis is a a. Water borne disease b. Air borne disease c. Food borne disease d. Atthropod borne disease |
|
Answer» Tuberculosis is a Airborne disease. |
|
| 95288. |
The ability of Microscope to distinguish two objects into two separate objects, is called. a. Resolving power b. Wave length c. N.A. d. None of these |
|
Answer» a. Resolving power |
|
| 95289. |
The resolution power of the compound microscope is a. 0.2 micron b. 0.2 millimeter c. 0.2 Angstrom units d. 0.2 centimeter |
|
Answer» The resolution power of the compound micro scope is 0.2 micron. |
|
| 95290. |
Light gathering capacity of Microscope is called a. Numerical aperture b. Angular aperture c. Both a and b d. None of these |
|
Answer» Light gathering capacity of Microscope is called Numerical aperture. |
|
| 95291. |
Streptococcus pneumoniae was isolated by a. Robert Koch b. Edward Jenner c. Antony von Leewenhock d. Louis Pasteur |
|
Answer» Streptococcus pneumoniae was isolated by Louis Pasteur. |
|
| 95292. |
L – forms are discovered by a. Klein Berger b. Louis Pasteur c. Robert Koch d. Antony von Leeuwenhock |
|
Answer» L – forms are discovered by Klein Berger. |
|
| 95293. |
Staphylococcus aureus was isolated by a. Rosenbach b. Louis Pasteur c. Passet d. Sir Alexander Ogston |
|
Answer» Staphylococcus aureus was isolated by Louis Pasteur. |
|
| 95294. |
Phagocytic phenomenon was discovered by a. Louis Pasteur b. Alexander Fleming c. Metchnikoff d. Robert Koch |
|
Answer» Phagocytic phenomenon was discovered by Metchnikoff. |
|
| 95295. |
Limit of resolution of compound microscope is a. 0.018 Åb. 0.1 mm c. 5 ìm d. 1 mm |
|
Answer» Limit of resolution of compound microscope is 0.1 mm. |
|
| 95296. |
Who perfected a magnetic lens in 1927 a. Gabor b. Broglie c. Busch d. None of these |
|
Answer» Who perfected a magnetic lens in 1927 Gabor. |
|
| 95297. |
Pseudomonas aeruginosa was first named a. Schroeter and Gessard b. Robert Koch c. Louis Pasteur d. Edward Jenner |
|
Answer» Pseudomonas aeruginosa was first named Schroeter and Gossard. |
|
| 95298. |
Mycobacterium lepree was discovered by a. Robert Koch b. Hansen c. Edward Jenner d. Louis Pasteur |
|
Answer» Mycobacterium leper was discovered by Hansen. |
|
| 95299. |
Source of light in fluorescence microscopy is from a. Mercury lamp b. Sunlight c. Both a and b d. None of these |
|
Answer» Source of light in fluorescence microscopy is from Mercury lamp. |
|
| 95300. |
Rh factor of the blood was discovered by scientist a. Louis Pasteur b. Landsteiner and Weiner c. Janskey d. Moss e. None of these |
| Answer» b. Landsteiner and Weiner | |