JEE Main 2012 Previous Year Question Paper with Solutions

The increasing order of the ionic radii of the given isoelectronic species is:

The density of a solution prepared by dissolving of urea (mol. Mass ) in of water is . The molarity of this solution is :

How many chiral compounds are possible on monochlorination of 2-methyl butane?

In which of the following pairs the two species are not isostructural ?

The compressibility factor for a real gas at high pressure is:

The standard reduction potentials for , and are and respectively. The reaction will be spontaneous when :

Which branched chain isomer of the hydrocarbon with molecular mass gives only one isomer of mono substituted alkyl halide ?

The electrons identified by quantum numbers and :(a) (b) (c) (d) Can be placed in order of increasing energy as :

In the given transformation, which of the following is the most appropriate reagent?

The molecule having smallest bond angle is :

Which one of the following statements is correct ?

2-Hexyne gives trans-2-Hexene on treatment with:

The equilibrium constant for the reaction at temperature is . The value of for the reaction, at the same temperature is:

What is DDT among the following?

Iron exhibits and oxidation states. Which of the following statements about iron is incorrect?

For a first order reaction, (A) products, the concentration of A changes from to in 40 minutes. The rate of reaction when the concentration of is is:

Ortho-Nitrophenol is less soluble in water than - and - Nitrophenols because:

Lithium forms body centred cubic structure. The length of the side of its unit cell is . Atomic radius of the lithium will be:

for water is . If your automobile radiator holds of water, how many grams of ethylene glycol must you add to get the freezing point of the solution lowered to ?

Iodoform can be prepared from all except :

Which of the following compounds can be detected by Molisch's test?

Which among the following will be named as dibromidobis (ethylene diamine) chromium(III) bromide?

The of a molar solution of the acid is 3 . The value of the ionization constant, of this acid is

The incorrect expression among the following is :

Assuming the balls to be identical except for difference in colours, the number of ways in which one or more balls can be selected from 10 white, 9 green and 7 black balls is:

A spherical balloon is filled with cubic meters of helium gas. If a leak in the balloon causes the gas to escape at the rate of cubic meters per minute, then the rate (in meters per minute) at which t

If the line and intersect, then is equal to:

Let be such that the function given by has extreme values at and Statement-1: has local maximum at and at .Statement-2: and

The area between the parabolas and and the straight line is:

The population at time of a certain mouse species satisfies the differential equation . If , then the time at which the population becomes zero is :

If and is real, then the point represented by the complex number lies :

Let . If and are column matrices such that and , then is equal to :

If the , then is equal to:

Let be observations, and let be their arithmetic mean and be their variance.Statement 1 : Variance of is .Statement : Arithmetic mean of is .

The equation has:

A line is drawn through the point to meet the coordinate axes at and such that it forms a triangle , where is the origin. If the area of the triangle is least, then the slope of the line is :

If , then equals

If is a function defined by where denotes the greatest integer function, then is

Three numbers are chosen at random without replacement from . The probability that their minimum is 3 , given that their maximum is 6 , is :

Let and be matrices . If and then determinant of is equal to:

Let . The number of different ordered pairs that can be formed such that and is empty, is :

A equation of a plane parallel to the plane and at a unit distance from the origin is:

Consider the function, Statement - Statement is continuous in , differentiable in and

A wooden wheel of radius is made of two semicircular part (see figure). The two parts are held together by a ring made of a metal strip of cross sectional area and length is slightly less than . To fi

Assume that a neutron breaks into a proton and an electron. The energy released during this process is : (mass of neutron , mass of proton , mass of electron

Proton, deuteron and alpha particle of same kinetic energy are moving in circular trajectories in a constant magnetic field. The radii of proton, denuteron and alpha particle are respectively and . Wh

A charge is uniformly distributed over the surface of non-conducting disc of radius . The disc rotates about an axis perpendicular to its plane and passing through its center with an angular velocity

A particle of mass is at rest at the origin at time . It is subjected to a force in the direction. Its speed is depicted by which of the following curves?

In Young's double slit experiment, one of the slit is wider than other, so that amplitude of the light from one slit is double of that from other slit. If be the maximum intensity, the resultant inten

A cylindrical tube, open at both ends, has a fundamental frequency, , in air. The tube is dipped vertically in water so that half of it is in water. The fundamental frequency of the aircolumn is now:

The figure shows an experimental plot for discharging of a capacitor in an R-C circuit. The time constant of this circuit lies between

A boy can throw a stone up to a maximum height of . The maximum horizontal distance that the boy can throw the same stone up to will be

The mass of a spaceship is . It is to be launched from the earth's surface out into free space. The value of and (radius of earth) are and respectively. The required energy for this work will be:

A coil is suspended in a uniform magnetic field, with the plane of the coil parallel to the magnetic lines of force. When a current is passed through the coil it starts oscillating; It is very difficu

A liquid in a beaker has temperature at time and is temperature of surroundings, then according to Newton's law of cooling the correct graph between and is:

An object in front of a lens forms a sharp image on a film behind the lens. A glass plate thick, of refractive index is interposed between lens and film with its plane faces parallel to film. At what

This question has statement- 1 and statement- 2. Of the four choices given after the statements, choose the one that best describe the two statements.An insulating solid sphere of radius has a uniform

An electromagnetic wave in vacuum has the electric and magnetic field and , which are always perpendicular to each other. The direction of polarization is given by and that of wave propagation by . Th

Resistance of a given wire is obtained by measuring the current flowing in it and the voltage difference applied across it. If the percentage errors in the measurement of the current and the voltage d

A Carnot engine, whose efficiency is , takes in heat from a source maintained at a temperature of . It is desired to have an engine of efficiency . Then, the intake temperature for the same exhaust (s

A diatomic molecule is made of two masses and which are separated by a distance . If we calculate its rotational energy by applying Bohr's rule of angular momentum quantization, its energy will be giv

If a simple pendulum has significant amplitude (up to a factor of of original ) only in the period between to , then may be called the average life of the pendulum When the spherical bob of the pendul

Helium gas goes through a cycle (consisting of two isochoric and isobaric lines) as shown in figure efficiency of this cycle is nearly : (Assume the gas to be close to ideal gas)

This question has Statement 1 and Statement 2 . Of the four choices given after the Statements, choose the one that best describes the two Statements.If two springs and of force constants and , respec

A spectrometer gives the following reading when used to measure the angle of a prism.Main scale reading: degreeVernier scale reading : 09 divisionsGiven that 1 division on main scale corresponds to de

Let and two unit vectors. If the vectors and are perpendicular to each other, then the angle between and is :

Let be a parallelogram such that and be an acute angle. If is the vector that coincide with the altitude directed from the vertex to the side , then is given by :

Hydrogen atom is excited from ground state to another state with principal quantum number equal to 4 . Then the number of spectral lines in the emission spectra will be :

Truth table for system of four gates as shown in figure is:

Two cars of masses and are moving in circles of radii and , respectively. Their speeds are such that they make complete circles in the same time t. The ratio of their centripetal acceleration is

This question has Statement 1 and Statement 2. Of the four choices given after the statements, choose the one that best describes the two statements.Statement 1 : Davisson - Germer experiment establis

A thin liquid film formed between a U-shaped wire and a light slider supports a weight of (see figure). The length of the slider is and its weight negligible. The surface tension of the liquid film is

In a uniformly charged sphere of total charge and radius , the electric field is plotted as function of distance from the center. The graph which would correspond to the above will be:

Two electric bulbs marked and are connected in series to a supply. Which of the bulbs will fuse?