Online IIT JEE Tests - Practice # 21

If for any reaction, the rate constant is equal to the rate of the reaction at all concentration, the order is;

For a certain reaction involving a single reactant, it is found that Co is constant where is the initial concentration of the reactant and T is the half-life. What is the order of the reaction?

The number of nodal planes in a orbital is

The orbital angular momentum of an electron in 2s orbital is

Answer the following 2 questions on the basis of the given paragraph.

Although Bohr’s Atomic Model is superior to Rutherford’s atomic model no doubt, still it is defective. In fact both models were suggested by considering the particle nature of electron, but wave nature of electron
was not considered by them. The optical phenomenon like scattering, interference, polarization, diffraction etc., can not be explained by considering the particle nature of electron. The quantum theory of radiation introduced by Plank and Einstein implies a particle theory of light, in addition to the wave theory of light required by the phenomenon of interference, diffraction. De Broglie argues that if light were composed by particles and yet showed wave like properties, the same should be true for the electrons and other particles. According to de-Broglie, an electron can behave like a matter as well as wave ;

greater the mass and velocity of the particle the shorter its wavelength. Since the wavelength associated with any macroscopic particle is smaller than the dimensions of any physical system, diffraction or other wave phenomenon can never be observed with a macroscopic particle. Another fundamental idea in wave mechanics is expressed by Heisenberg’s Uncertainly Principle (1927), which may be illustrated for an electron by considering the problem of determining its position and momentum. The general principles of optics tell us that it is impossible to locate the electron more accurately than to within photon used in looking for it.

or

It is therefore required to use radiation of shortest wavelength possible, but the action of the photon on the electron results in the transfer of some of the photons energy to the electron with a resultant increase in its velocity and momentum. Decreasing the wavelength of photon increases the margin of uncertainty in the momentum of electron, increasing the wavelength of the photon reduces the degree of resolution possible and increases the uncertainty in the position of the electron.

In fact, it suggest the concept of orbital within which the probability of finding electron will be maximum.

Alveoli are the tiny sacs of air in the lungs whose average diameter is 50 pm. Consider an oxygen molecule trapped within a sac. Calculate uncertainty in the velocity of oxygen molecule –

. Determine the de-Broglie wavelength associated with an electron in the .Bohr’s orbit of ion –

Answer the following four question which are given below

In each of the following question, a statement of Assertion (A) is given and a corresponding statement of Reason® is given just below it. Of the statement, mark the correct aanswer as;

. Assertion: The order of a reaction may be negative.

Reason: In some cases, the rate of reaction decreases as the concentration of the reactant increases.

. Assertion: The kinetic of the reaction –

obeys the rate of

expression as .

Reason: The rate of the reaction does not depend upon the concentrations of C.

. Assertion: is a colured ion.

Reason: Every ion with unpaired electron is colured.

. . Assertion: The paramagnetism of ion is zero.

Reason: Paramagnetism is given by the relation magnetons where S is the total spin

Which is the first carbon compound in the ketone group?

While cooking if vessel’s bottom gets blackened on the outside, it means that

10ml of a solution of NaOH is found neutralized by 8ml of given solution of HCl. If we take 20ml of same solution of NaOH, the amount of HCl solution required to neutralize it will be:

A solution reacts with crushed egg-shells to give a gas that turns lime water milky.The solution contains:

Which is used in treating indigestion?