Copper can be extracted from:
(A) Cryolite
(B) Malachite
(C) Calamine
(D) Copper glance
(E) Cuprite
Choose the correct answer from the options given below :

Read the passage carefully and answer the questions
Replacement of a hydrogen atom in a hydrocarbon by an alkoxy or carboxyl group yields a class of compounds known as ethers. Ethers are classified as symmetrical or unsymmetrical on the basis of groups attached to the oxygen atoms. Diethyl ether, a symmetrical ether, has been widely used as an inhalation anesthetic. Ethers can be prepared by acid catalyzed intermolecular dehydration of alcohols and Williamson's synthesis. Acid catalyzed dehydration of alcohols is not generally preferred as it gives a mixture of elimination and substitution products. In Williamson's synthesis, an alkyl halide is allowed to react with sodium alkoxide. Ethers containing substituted Alkyl groups may also be prepared by this method. The C-O bond in ether is weakly polar and is cleaved under drastic conditions with excess of hydrogen halides. In electrophilic substitution, the alkoxy group deactivates the aromatic ring and directs the incoming group to ortho and para positions.
Which is most reactive hydrogen halide for cleavage of ethers?

Minimum boiling azeotropes show __________ deviation from Raoult's Law at a specific composition.

The C-O-H bond angle in alcohols is slightly less than tetrahedral angle \(109^{\circ} 28^{\prime}\) due to:

"Answer the question on basis of passage given below :
Carboxylic acids are weaker than mineral acids, but they are stronger acids than alcohols and many simple phenols (\(\text{pKa}\) is ~ 16 for ethanol and 10 for phenol). The higher acidity of carboxylic acids as compared to phenols can be understood similarly. The conjugate base of carboxylic acid, a carboxylate ion, is stabilised by two equivalent resonance structures in which the negative charge is at the more electronegative oxygen atom. The conjugate base of phenol, a phenoxide ion, has non-equivalent resonance structures in which the negative charge is at the less electronegative carbon atom. Further, the negative charge is delocalised over two electronegative oxygen atoms in carboxylate ion whereas it is less effectively delocalised over one oxygen atom and less electronegative carbon atoms in phenoxide ion. Thus, the carboxylate ion is more estabilised than phenoxide ion, so carboxylic acids are more acidic than phenols.
Effect of substituents on the acidity of carboxylic acids: substituents may affect the stabliity of the conjugate base and thus, also affect the acidity of the carboxylic acids. Electron withdrawing group increase the acidity of carboxylic acids by stabilising the conjugate base through delocalisation of the negative charge by inductive and/or resonance effects. Conversely, electron donating groups decrease the acidity by destabilising the conjugate base.
Which of the following compounds would have the smallest value of \(\text{pKa}\)?"

Which of the following shows both, Frenkel and Schottky defect ?

Read the passage carefully and answer the Questions
The decomposition of \(N_2O_5\ (g)\) is given as
\(N_2O_5(g) \rightarrow 2NO_2(g) + \frac{1}{2}O_2(g)\)
The above reaction is found to be of first order.
Choose the correct statement about the rate of the reaction:

Identify the INCORRECT statement(s) in the context of phenomenon of interference.
1. All bright and dark fringes have equal width.
2. All bright fringes have the same intensity.
3. Fringe width depends on the distance of screen from the slits.
4. All dark and bright fringes are not equally spaced.
Choose the correct answer from the options given below:

Cyclosporin A, which is used as an immunosuppressive agent, is produced by:

In the Block diagram of a generalised communication system, the elements are given below. The correct order of elements should be :
(A) Transmitter
(B) Information Source
(C) User of Information
(D) Channel
(E) Receiver
Choose the correct answer from the options given below:

what is Mohr's salt colour ?

Let a pair of dice be thrown and the random variable \(X\) be the sum of the numbers that appear on the two dice.
Match List - I with List - II

X	Probability, \(P ( X )\)
(A) 4	(I) \(\frac{1}{6}\)
(B) 5	(II) \(\frac{5}{36}\)
(C) 6	(III) \(\frac{1}{12}\)
(D) 7	(IV) \(\frac{1}{9}\)

Choose the correct answer from the options given below :

The term 'Linkage' was given by