NEET 2018 | NEET Year Wise Previous Years Questions

Biology

Chemistry

1. A mixture of 2.3 g formic acid and 4.5 g oxalic acid is treated with conc. H2SO4 . The evolved gaseous mixture is passed 2. In which case is number of molecules of water maximum? 3. Which one is a wrong statement? 4. The correct order of atomic radii in group 13 elements is 5. Which of the following oxides is most acidic in nature? 6. Consider the following species : CN+ , CN– , NO and CN. Which one of these will have the highest bond order? 7. The correction factor ‘a’ to the ideal gas equation corresponds to 8. The bond dissociation energies of X2 , Y2 and XY are in the ratio of 1 : 0.5 : 1. $$\Delta $$H for the formation of XY 9. Given van der Waals’ constant for NH3 , H2, O2 and CO2 are respectively 4.17, 0.244, 1.36 and 3.59, which one of the f 10. In the structure of ClF3 , the number of lone pairs of electrons on central atom ‘Cl’ is 11. The solubility of BaSO4 in water is 2.42 × 10–3 g L–1 at 298 K. The value of its solubility product (Ksp) will be (Give 12. Following solutions were prepared by mixing different volumes of NaOH and HCl of different concentrations : A. 60 mL $${ 13. Which one of the following conditions will favour maximum formation of the product in the reaction A2(g) + B2(g) ⇌ X2(g 14. For the redox reaction, MnO4– + C2O4 2– + H+ $$ \to $$ Mn2+ + CO2 + H2O The correct coefficients of the reactants for 15. Consider the change in oxidation state of bromine corresponding to different emf values as shown in the given diagram : 16. The correct order of N-compounds in its decreasing order of oxidation states is 17. Among CaH2 , BeH2 , BaH2 , the order of ionic character is 18. Which of the following is correct with respect to – I effect of the substituents? (R = alkyl) 19. Which one of the following elements is unable to form MF63– ion? 20. Magnesium reacts with an element (X) to form an ionic compound. If the ground state electronic configuration of (X) is 1 21. Which of the following molecules represents the order of hybridisation sp2 , sp2 , sp, sp from left to right atoms? 22. Which of the following carbocations is expected to be most stable? 23. Which oxide of nitrogen is not a common pollutant introduced into the atmosphere both due to natural and human activity? 24. Hydrocarbon (A) reacts with bromine by substitution to form an alkyl bromide which by Wurtz reaction is converted to gas 25. Iron exhibits bcc structure at room temperature. Above 900°C, it transforms to fcc structure. The ratio of density of ir 26. The correct difference between first and second order reactions is that 27. On which of the following properties does the coagulating power of an ion depend? 28. Considering Ellingham diagram, which of the following metals can be used to reduce alumina? 29. When initial concentration of the reactant is doubled, the half-life period of a zero order reaction 30. Which of the following statements is not true for halogens? 31. Which one of the following ions exhibits d-d transition and paramagnetism as well? 32. Match the metal ions given in Column I with the spin magnetic moments of the ions given in Column II and assign the corr 33. The type of isomerism shown by the complex [CoCl2(en)2] is 34. The geometry and magnetic behaviour of the complex [Ni(CO)4] are 35. The compound A on treatment with Na gives B, and with PCl5 gives C. B and C react together to give diethyl ether. A, B 36. Iron carbonyl, Fe(CO)5 is 37. In the reaction, the electrophile involved is 38. Compound A, C8H10O, is found to react with NaOI (produced by reacting Y with NaOH) and yields a yellow precipitate with 39. The compound C7H8 undergoes the following reactions : The product ‘C’ is 40. Identify the major products P, Q and R in the following sequence of reactions : 41. Carboxylic acids have higher boiling points than aldehydes, ketones and even alcohols of comparable molecular mass. It i 42. Nitration of aniline in strong acidic medium also gives m-nitroaniline because 43. The difference between amylose and amylopectin is 44. Which of the following compounds can form a zwitter ion? 45. Regarding cross-linked or network polymers, which of the following statements is incorrect?

Physics

1. A student measured the diameter of a small steel ball using a screw gauge of least count 0.001 cm. The main scale readin 2. Which one of the following statements is incorrect? 3. A moving block having mass m, collides with another stationary block having mass 4m. The lighter block comes to rest aft 4. A block of mass m is placed on a smooth inclined wedge ABC of inclination q as shown in the figure. The wedge is given a 5. A body initially at rest and sliding along a frictionless track from a height h (as shown in the figure) just completes 6. A solid sphere is in rolling motion. In rolling motion a body possesses translational kinetic energy (Kt) as well as rot 7. A solid sphere is rotating freely about its symmetry axis in free space. The radius of the sphere is increased keeping i 8. The power radiated by a black body is P and it radiates maximum energy at wavelength, $$\lambda $$0 . If the temperature 9. Three objects, A : (a solid sphere), B : (a thin circular disk) and C : (a circular ring), each have the same mass M and 10. The kinetic energies of a planet in an elliptical orbit about the Sun, at positions A, B and C are KA, KB and KC, respec 11. Two wires are made of the same material and have the same volume. The first wire has cross-sectional area A and the seco 12. The efficiency of an ideal heat engine working between the freezing point and boiling point of water, is 13. The moment of the force, $$\overrightarrow F = 4\widehat i + 5\widehat j - 6\widehat k$$ at (2, 0, –3), about the point 14. A sample of 0.1 g of water at 100°C and normal pressure (1.013 × 105 N m–2) requires 54 cal of heat energy to convert t 15. The volume (V) of a monatomic gas varies with its temperature (T), as shown in the graph. The ratio of work done by the 16. A small sphere of radius ‘r’ falls from rest in a viscous liquid. As a result, heat is produced due to viscous force. Th 17. If the mass of the Sun were ten times smaller and the universal gravitational constant were ten times larger in magnitud 18. The fundamental frequency in an open organ pipe is equal to the third harmonic of a closed organ pipe. If the length of 19. A tuning fork is used to produce resonance in a glass tube. The length of the air column in this tube can be adjusted by 20. A pendulum is hung from the roof of a sufficiently high building and is moving freely to and fro like a simple harmonic 21. The electrostatic force between the metal plates of an isolated parallel plate capacitor C having a charge Q and area A, 22. An electron falls from rest through a vertical distance h in a uniform and vertically upward directed electric field E. 23. At what temperature will the rms speed of oxygen molecules become just sufficient for escaping from the Earth’s atmosphe 24. A carbon resistor of (47 $$ \pm $$ 4.7) k$$\Omega $$ is to be marked with rings of different colours for its identificat 25. A battery consists of a variable number n of identical cells (having internal resistance r each) which are connected in 26. A set of n equal resistors, of value R each, are connected in series to a battery of emf E and internal resistance R. Th 27. A toy car with charge q moves on a frictionless horizontal plane surface under the influence of a uniform electric field 28. A metallic rod of mass per unit length 0.5 kg m–1 is lying horizontally on a smooth inclined plane which makes an angle 29. A thin diamagnetic rod is placed vertically between the poles of an electromagnet. When the current in the electromagnet 30. The magnetic potential energy stored in a certain inductor is 25 mJ, when the current in the inductor is 60 mA. This ind 31. Current sensitivity of a moving coil galvanometer is 5 div/mA and its voltage sensitivity (angular deflection per unit v 32. An inductor 20 mH, a capacitor 100 $$\mu $$F and a resistor 50 $$\Omega $$ are connected in series across a source of em 33. The refractive index of the material of a prism is $$\sqrt 2 $$ and the angle of the prism is 30°. One of the two refrac 34. An EM wave is propagating in a medium with a velocity $$\overrightarrow v = v\widehat i$$. The instantaneous oscillatin 35. An object is placed at a distance of 40 cm from a concave mirror of focal length 15 cm. If the object is displaced throu 36. In Young’s double slit experiment the separation d between the slits is 2 mm, the wavelength $$\lambda $$ of the light u 37. Unpolarised light is incident from air on a plane surface of a material of refractive index $$\mu $$. At a particular an 38. An astronomical refracting telescope will have large angular magnification and high angular resolution, when it has an o 39. An electron of mass m with an initial velocity $$\overrightarrow v = {v_0}\widehat i$$ (v0 > 0) enters an electric 40. When the light of frequency 2$${\upsilon _0}$$ (where $${\upsilon _0}$$ is threshold frequency), is incident on a meta 41. In the circuit shown in the figure, the input voltage Vi is 20 V, VBE = 0 and VCE = 0. The values of IB , IC and $$\bet 42. For a radioactive material, half-life is 10 minutes. If initially there are 600 number of nuclei, the time taken (in min 43. In the combination of the following gates the output Y can be written in terms of inputs A and B as 44. The ratio of kinetic energy to the total energy of an electron in a Bohr orbit of the hydrogen atom, is 45. In a p-n junction diode, change in temperature due to heating

NEET 2018

MCQ (Single Correct Answer)

-1

An object is placed at a distance of 40 cm from a concave mirror of focal length 15 cm. If the object is displaced through a distance of 20 cm towards the mirror, the displacement of the image will be

30 cm away from the mirror

36 cm away from the mirror

30 cm towards the mirror

36 cm towards the mirror

NEET 2018

MCQ (Single Correct Answer)

-1

In Young’s double slit experiment the separation d between the slits is 2 mm, the wavelength $$\lambda $$ of the light used is 5896 $$\mathop A\limits^0 $$ and distance D between the screen and slits is 100 cm. It is found that the angular width of the fringes is 0.20^o. To increase the fringe angular width to 0.21^o (with same $$\lambda $$ and D) the separation between the slits needs to be changed to

1.9 mm

1.8 mm

2.1 mm

1.7 mm

NEET 2018

MCQ (Single Correct Answer)

-1

Unpolarised light is incident from air on a plane surface of a material of refractive index $$\mu $$. At a particular angle of incidence i, it is found that the reflected and refracted rays are perpendicular to each other. Which of the following options is correct for this situation?

Reflected light is polarised with its electric vector parallel to the plane of incidence

Reflected light is polarised with its electric vector perpendicular to the plane of incidence

$$i = {\sin ^{ - 1}}\left( {{1 \over \mu }} \right)$$

i = tan^-1$$\left( {{1 \over \mu }} \right)$$

NEET 2018

MCQ (Single Correct Answer)

-1

An astronomical refracting telescope will have large angular magnification and high angular resolution, when it has an objective lens of

small focal length and large diameter

large focal length and small diameter

large focal length and large diameter

small focal length and small diameter