Alkyl halides react with dialkyl copper reagents to give
During dehydration of alcohols to alkenes by heating with concentrated H2SO4 the initiation step is
Among the following compounds which can be dehydrated very easily?
Phenyl magnesium bromide reacts with methanol to give
Which one of the following undergoes reaction with 50% sodium hydroxide solution to give the corresponding alcohol and acid?
Which one of the following is reduced with zinc and hydrochloric acid to give the corresponding hydrocarbon?
When primary amine reacts with chloroform in ethanoic KOH then the product is
The correct order of increasing basic nature for the bases NH3, CH3NH2 and (CH3)2NH is
Which one of the following methods is neither meant for the synthesis nor for separation of amines?
Which one of the following is the strongest base in aqueous solution?
The species which can best serve as an initiator for the cationic polymerization is
The reason for double helical structure of DNA is operation of
The term anomers of glucose refers to
The two functional groups present in a typical carbohydrate are
Which one of the following groupings represents a collection of isoelectronic species? (At. nos.: Cs-55, Br-35)
Which one of the following ions has the highest value of ionic radius?
The increasing order of the first ionisation enthalpies of the elements B, P, S and F (lowest first) is
Which one of the following ores is best concentrated by froth flotation method?
The number of hydrogen atom(s) attached to phosphorus atom in hypophosphorous acid is
Very pure hydrogen (99.9%) can be made by which of the following processes?
KO2 (potassium super oxide) is used in oxygen cylinders in space and submarines because it
In curing cement plasters, water is sprinkled from time to time. This helps in
Several blocks of magnesium are fixed to the bottom of a ship to
The solubilities of carbonates decrease down the magnesium group due to a decrease in
Based on lattice energy and other consider cations which one of the following alkali metal chlorides is expected to have the highest melting point?
The ionic mobility of alkali metal ions in aqueous solution is maximum for
Which one of the following alkaline earth metal sulphates has its hydration enthalpy greater than its lattice enthalpy?
Among Al2O3, SiO2, P2O3 and SO2 the correct order of acid strength is
A sample of a hydrate of barium chloride weighing 61 g was heated until all the water of hydration is removed. The dried sample weighed 52 g. The formula of the hydrated salt is: (atomic mass, Ba = 137 amu, Cl = 35.5 amu)
Which of the following is not an assumption of the kinetic theory of gases?
If the principal quantum number n=6, the correct sequence of filling of electrons will be:
The heat of atomization of methane and ethane are 360 kJ/mol and 620 kJ/mol, respectively. The longest wavelength of light capable of breaking the C - C bond is (Avogadro number = 6.02×1023, h = 6.62×10-34 J s):
A solution at 20°C is composed of 1.5 mol of benzene and 3.5 mol of toluene. If the vapour pressure of pure benzene and pure toluene at this temperature are 74.7 torr and 22.3 torr, respectively, then the total vapour pressure of the solution and the benzene mole fraction in equilibrium with it will be, respectively:
A stream of electrons from a heated filament was passed between two charged plates kept at a potential difference V esu. If e and m are charge and mass of an electron, respectively, then the value of h/λ (where λ is wavelength associated with electron wave) is given by:
For a linear plot of log (x/m) versus log p in a Freundlich adsorption isotherm, which of the following statements is correct ? (k and n are constants)
The heats of combustion of carbon and carbon monoxide are –393.5 and –283.5 kJ mol–1, respectively. The heat of formation (in kJ) of carbon monoxide per mole is:
18 g glucose (C6H12O6) is added to 178.2 g water. The vapour pressure of water (in torr) for this aqueous solution is:
The distillation technique most suited for separating glycerol from spent-lye in the soap industry is:
Decomposition of H2O2 follows a first order reaction. In fifty minutes the concentration of H2O2 decreases from 0.5 to 0.125 M in one such decomposition. When the concentration of H2O2 reaches 0.05 M, the rate of formation of O2 will be: