Which of the following is not a cause of lanthanoid contraction?

Arrange the following elements in decreasing order of their radii:
(A) La
(B) Pr
(C) Gd
(D) Yb
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The elevation in boiling point will be maximum in

Read the passage carefully and answer the questions
The osmotic pressure is one of the four colligative properties which depends on the number of particles of solute in the solution, irrespective of their nature. The osmotic pressure is equal to the product of concentration, gas constant and temperature. It is the most commonly used property for the determination of the molar mass of biomolecules. In many situations, the molecules get dissociated or associated when they are dissolved in a solvent, thereby changing the number of molecules in the solution. As a result, an abnormal molecular mass is obtained. The extent of dissociation or association is given by van't Hoff factor (i), which is the ratio of normal molar mass to abnormal molar mass. It is related with the degree of association or ionization. The introduction of van't Hoff factor in the osmotic pressure equation modifies the equation.
The osmotic pressure of a 0.1 M aqueous solution of \(K _2 SO _4\) is 4.92 atmat300 K. The percentage ionization of the salt is: Given \(R =0.082 atm L K ^{-1} mol^{-1}\)

The correct sequence of steps during the corrosion of iron is
(A) Ferrous ions are oxidized by atmospheric oxygen
(B) Hydrated ferric oxide (\(\text{Fe}_2\text{O}_3 \cdot \text{H}_2\text{O}\)) formed with production of \(\text{H}^{+}\) ions
(C) At a particular spot of iron object, oxidation takes place and that spot behaves as anode
(D) Electron released at anode moves through metal and reduces oxygen in the presence of \(\text{H}^{+}\)
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Why do the actinoids exhibit a higher number of oxidation states than lanthanoids?

Question based on following passage :
Adsorption is the process of attracting and retaining the adsorbate molecules on the surface of adsorbent. It is of two types i.e. Physisrption and chemisorption. To increase the rate of reaction, the substance called 'catalyst' is added. Promotors enhance the activity of catalyst while poison decrease the catalyst activity. Solutions may be true solution, suspension and colloids. Colloids are heterogenous but quite stable. On the basis of nature of interaction, colloids may be Lyophilic or Lyophobic. On the basis of type of dispersed phase particles, there may be multimolecular colloids, macromlecular colloids and associated colloids. The congulation of colloids may be done by boiling, dialysis or by mixing oppositely charged sols.
The best coagulating agent for \(Fe(OH)_3\) solution is :

Homologous structures have :

1. An electron of mass m is moving with kinetic energy k and momentum p. The de-Broglie wavelength associated will be :
(A) \( \lambda = \frac{\sqrt{2mk}}{p} \)
(B) \( \lambda = \frac{p}{h} \)
(C) \( \lambda = \frac{h}{p} \)
(D) \( \lambda = \frac{h}{\sqrt{2mk}} \)
Choose the correct answer from the options given below :

It is difficult to separate the ores of Zr and Hf because:

The organisation set up by the Indian Government to take decisions regarding the validity of GM research and the safety of introducing GM-organism is:

Match List-I (compound) with List-II (reagent or chemical test)

List-I (Compound)	List-II (Reagent or Chemical test)
(A) Phenols	(I) Tollen's test
(B) Amines	(II) \(NeutralFeCl _3 aq\). solution
(C) Aldehydes	(III) Iodoform Test
(D) Methyl Ketones	(IV) Hinsberg's Test

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The rate constant for a reaction is \(3.5 \mathrm{~mol}^{-1} \mathrm{~L} \mathrm{~s}-^{-1}\). The order of the reaction is: