Chlorine containing antibiotic produced by soil microorganisms which is effective for the treatment of typhoid fever is :

The correct sequence of conductivity of the following materials at 300 K in the increasing order is
(A) Copper
(B) Graphite
(C) Germanium
(D) Silicon
Choose the correct answer from the options given below:

What are the number of chiral centers in the given Alkyl halide

Interstitial compounds are formed when small atoms like H, C, or N are trapped in the crystal lattice of metal. Which of the following statements are true about the interstitial compounds?
(A) Interstitial compounds have higher melting points than the pure metals.
(B) Interstitial compounds are very soft.
(C) Interstitial compounds are very reactive.
(D) Interstitial compounds retain metallic conductivity.
Choose the correct answer from the options given below:

Derive the electronic configuration of \(Ce ^{3+}\) ion by using Hund's rule.

Which of the following statements about the rate of a chemical reaction are correct?
(A) The rate of reaction is always proportional to the concentration of reactants
(B) An exponential time course is followed by the first order reaction
(C) The unit of rate of reaction in the gaseous state is atm/s
(D) The concentration of reactant decreases exponentially with time for a zero order reaction
Choose the correct answer from the options given below:

Which of the following amines can be prepared by Gabriel synthesis ?
(A) Isobutyl amine
(B) 2-Phenyl ethylamine
(C) N-Methyl benzyl amine
(D) Aniline
Choose the correct answer from the options given below:

Answer the question on the basis of passage given below:
Proteins are the polymers of about twenty different a-amino acids which are linked by peptide bonds. Proteins perform various structural and dynamic functions in the organisms. Proteins which contain only a-amino acids are called simple proteins. The secondary or tertiary structure of proteins get disturbed on change of pH or temperature and they are not able to perform their functions. This is called denaturation of proteins. Enzymes are biocatalysts which speed up the reactions in biosystems. Vitamins are accessory food factors required in the diet. They are classified as fat soluble (A, D, E and K) and water soluble (B group and C). Deficiency of vitamins leads to many diseases. Nucleic acids are the polymers of nucleotides which in turn consist of a base, a pentose sugar and phosphate moiety. Nucleic acids are responsible for the transfer of characters from parents to offsprings. There are two types of nucleic acids DNA and RNA. DNA contains a five carbon sugar molecule called 2-deoxyribose whereas RNA contains ribose.
Which of the following is an essential amino acid?

A diverging lens of glass (\( \mu = 1.5 \)) has both surfaces of the same radius of curvature (R). On immersion in a medium of refractive index (\( \mu = 1.8 \)), it will behave as:

The resistance of a cylindrical conductor is :

The chemical formula of Magnetite is :

The current and voltage in an a. c. circuit are given as
\( I = 50 \sin(50t) \text{ mA} \),
\( V = 100 \sin(50t + \pi/3) \text{ volt} \).
The power dissipated in the circuit is

A metallic wire of uniform area of cross section has a resistance \(R\), resistivity \(\rho\) and power rating P at V volts. The wire is uniformly stretched to reduce the radius to half the original radius. The values of resistance, resistivity and power rating at V volts are now denoted by \(R ^{\prime}, \square\) ' and \(P ^{\prime}\) respectively. The corresponding values are correctly related as ___________ . Fill in the blank with the correct answer from the options given below