The molality of solution obtained by dissolving 1.5 g of ethanoic acid \(CH _3 COOH\) in \(2 5 ~ g\) of benzene is :

\(t_{99\%}\) with respect to \(t_{90\%}\) for a first order reaction is :

Which of the following statement is false?

Mischmetall consists of a lanthanoid metal (95\(\%\)) and Iron (~5\(\%\)) and traces of S, C, Ca \(\&\) Al. Mischmetall used for producing bullets contains:

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Aldehydes and ketones are important organic compounds prepared mainly by oxidation of alcohols. Primary alcohols give aldehyde and secondary alcohols yield ketones. Aldehydes can also be formed by partial reduction of acid chlorides, reduction
of esters or by Gattermann-Koch reaction. Ketones are prepared by Friedel-Craft's acylation, hydration of alkyne and reaction of Grignard's reagent with nitriles. Chemically, aldehydes and ketones are reactive in nature due to the carbonyl group and undergo nucleophilic addition reactions. Aldehydes are more reactive than ketones and can be oxidized to carboxylic acids, while both can be reduced to alcohols or hydrocarbons and exhibit condensation reaction.
Hydration of propyne in the presence of \(H _2 SO _4\) and \(HgSO _4\) gives

Elements of group-15, 16 and 17 form compounds with hydrogen with general formula MH3, \(H2M\) and HX (called hydrogen halides). Stability of these hydrides, along with M-H bond strength and basic nature decreases down the group. Boiling point of these hydrides mainly depends on the strength of their inter molecular forces.
Which of the following is most basic among the following hydrides of group 16?

Which of the following is the correct order of second ionization enthalpy?

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Insulin consists of two short polypeptide chains- chain A and chain B, that are linked together by disulphide bridges. Some strains of Bacillus thuringiensis produce proteins that kill certain insects such as lepidopterans, coleopterans and dipterans. Bt toxin protein is converted into an active form of toxin due to the alkaline pH of the gut which solubilise the crystals. Transgenic animals that produce useful biological products can be created by the introduction of the portion of DNA (or genes) which codes for a particular product such as human protein (alpha-1-antitrypsin) used to treat emphysema. Plants, bacteria, fungi and animals whose genes have been altered by manipulation are called Genetically Modified Organisms (GMO). GM plants have been useful in many ways. Genetic modification has: (i) made crops more tolerant to abiotic stresses. (ii) reduced reliance on chemical pesticides (pest-resistant crops). (iii) helped to reduce post harvest losses. (iv) increased efficiency of mineral usage by plants (this prevents early exhaustion of fertility of soil). (v) enhanced nutritional value of food.
Which one of the followings is not true about insulin?

Two cylindrical wires of the same material have their lengths in the ratio 2: 1 and their diameters in the ratio \(1: 3\). The ratio of the resistance of thinner wire to that of thicker wire is:

Due to which of the following, the irregular variations in a time series are caused:
(A) Floods
(B) Rise in prices before festivals
(C) A fire in a factory
(D) Epidemics
Choose the correct answer from the options given below:

Which of the following is NOT a property of charges?

The mathematical expression that represents the Exponential growth in a population is:

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Antibiotics have greatly improved our capacity to treat deadly diseases such as plague, whooping cough (kali khansi), diphtheria (gal ghotu) and leprosy (kusht rog), which used to kill millions all over the globe.
Streptokinase produced by the bacterium Streptococcus and modified by genetic engineering is used as a 'clot buster' for removing clots from the blood vessels of patients who have undergone myocardial infarction leading to heart attack. Microbes are diverse-protozoa, bacteria, fungi and microscopic animal and plant viruses, viroids and also prions that are proteinacious infectious agents. The puffed-up appearance of dough is due to the production of CO₂ gas. Similarly the dough, which is used for making bread, is fermented using baker's yeast (Saccharomyces cerevisiae). Primary sewage treatment basically involve physical removal of particles - large and small from the sewage through filtration and sedimentation. These are removed in stages; initially, floating debris is removed by sequential filtration. Then the grit (soil and small pebbles) are removed by sedimentation. All solids that settle form the primary sludge, and the supernatant forms the effluent. The effluent from the primary settling tank is taken for secondary treatment. The primary effluent is passed into large aeration tanks, where it is constantly agitated mechanically and air is pumped into it. This allows vigorous growth of useful aerobic microbes into flocs. While growing, these microbes consume the major part of the organic matter in the effluent.
Genetically modified Streptokinase is used as a 'clot buster' for removing clots from the blood vessels is produced by :