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Define Van’t Hoff factor. How is it related to the degree of dissociation?

The ratio of real colligative characteristics to theoretical colligative properties is known as the Van't Hoff factor i. In other way the ratio... View Article

Which of the following is not a characteristic of pBR322 vector? A. It was the first artificial cloning vector constructed in 1977 by Bolivar and Rodriguez B. It is the most widely used, versatile and easily manipulated vector. C. It has two antibiotic resistance genes tetR and ampR. D. It does not have restriction site for Sall.

Answer: (d) Bolivar and Rodriguez created pBR322 in Herbert Boyer's laboratory at the University of California in 1977. To identify this... View Article

Bleaching action of chlorine is due to: A) reduction B) oxidation C) acidic effect D) basic effect

Answer: (a) Reduction Fabric is whitened by eliminating natural colours. Bleaching, for example, is used to tan linen. This is an example of... View Article

The reaction of Zinc with dilute and concentrated nitric acid ,respectively ,produces :

When zinc metal combines with dilute nitric acid, nitrous oxide, a colourless, non-flammable gas, is produced. Laughing gas is another name for... View Article

Which of the following are the characteristics of isotopes of an element? (i) isotopes of an element have the same atomic masses. (ii) isotopes of an element have the same atomic number. (iii) isotopes of an element show the same physical properties. (iv) isotopes of an element show the same chemical properties. A ) (i), (ii) and (iii) B ) (ii), (iii) and (iv) C ) (ii) and (iii) D ) (ii) and (iv)

Different atoms of the same atom are called isotopes. As a result, their atomic numbers are the same. The mass number of isotopes, however,... View Article

The boiling point of an azeotropic mixture of water and ethyl alcohol is less than that of the theoretical value of water and alcohol mixture. Hence the mixture shows:

An azeotropic mixture is one in which the vapour and fluid phases of the substances included in the combination have the same proportion.... View Article

Alkyl halides are immiscible in water though they are polar because?

The carbon-halogen linkages in alkyl halides are polar. The electronegativity of carbon and halogen differs significantly. Water is a polar... View Article

Mond process is used for refining of?

Ludwig Mond invented the Mond process in the year 1890. This technique is also known as the carbonyl process because it involves the rapid and... View Article

Which process can purify the impure sample of potash alum?

Answer: Crystallization Potash alum is a large subset of alum, which is one of the most often used coagulants in water treatment, especially... View Article

Which alcohol produces turbidity with lucas reagent most slowly?

Answer: Tertiary alcohols The -Lucas test is used to discriminate between different types of alcohol. The differential in reactivity of the... View Article

Which of the following is a chain growth polymer? A.) Teflon B.) Nylon-6,6 C.) Nylon-6 D.) None

Answer: (a) Teflon A chain growth polymer is one that is generated when molecules of the same or different monomers combine on a large scale... View Article

A brown ring is formed in the ring test for NO3- ion. It is due to the formation of:

The nitrate ion brown ring test is a qualitative test that verifies the presence of nitrate ion. A freshly produced ferrous sulphate solution is... View Article

Binary liquid mixture will show negative deviation from raoult’s law. Explain

According to Raoult's law, the partial vapour pressure of each component in a mixed solution is proportional to the pure component's vapour... View Article

Freon 12 is manufactured from tetrachloromethane by?

Freon-12 is made by CCl4 by the Swart's reaction, as shown below: 3CCl4 + 2SbF3 ⟶ 3CCl2F2(Freon−12) + 2SbCl3 Swarts’ reaction is generally used... View Article

The temperature coefficient of most of the reactions lies between:

Temperature coefficient is the ratio of rate constant of a reaction at a temperature and rate constant of the reaction when the temperature... View Article

Auto reduction process is used in the extraction of:

Sulphide ores containing less electropositive metals such as Cu, Hg, Pb, and others are heated in the presence of air in the auto reduction... View Article

o xylene on ozonolysis will give ?

Ozonolysis is a chemical process in which ozone causes the oxidative breakage of an unsaturated bond in a molecule. The final result will be an... View Article

Why is fluorine the most electronegative element?

The capacity of an element to establish chemical bonds by attracting an electron is measured by electronegativity. The capacity of an atom to... View Article

Which of the following properties generally decrease along a period? (A) Ionization energy (B) Electron affinity (C) Metallic character (D) Valency

Answer: (c) Metallic character Along a period the electropositive character decreases, therefore the ionization energy, electron affinity and... View Article

75.2 g of C6H5OH (Phenol) is dissolved in a solvent of Kf = 14 , If the depression in freezing point is 7K then find the % of phenol that dimerises.

According to the concept of freezing point depression whenever a solute is added to a pure solvent, the freezing point of the solvent (which is... View Article

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