List of practice Questions

More energy is released in fusion than fission. More number of nucleons take part in fission.
Assuming the earth to be a sphere of uniform density, the acceleration due to gravity inside the earth at a distance of $r$ from the centre is proportional to
Assume that a neutron breaks into a proton and an electron. The energy released during this process is : (Mass of neutron $= 1.6725 ??10^{-27}\, kg$, Mass of proton $= 1.6725 ??10^{-27}\, kg$, Mass of electron $= 9 ??10^{-31}\, kg$ )
van-Arkel method is used to prepare samples of some metals. It involves reaction of $CO$ with metals to form volatile carbonyls which decompose on heating to give pure metal.
The presence of nitro group facilitates nucleophilic substitution reactions in aryl halides. The intermediate carbanion is stabilised due to the presence of nitro group.
The free gaseous Cr atom has six unpaired electrons. Half-filled s-orbital has greater stability.
Sodium acetate on Kolbe?? electrolysis gives methane. Methyl free radical is formed at cathode.
Sodium carbonate extract of a salt containing sulphide ions gives a violet colour with appropriate reagent. The reagent sodium nitroprusside gives violet colour due to the formation of sodium thionitroprusside.
Precipitation of soap is made by the addition of salt $(NaCl)$. Presence of common ion suppresses the dissociation of weak acid.
Phenol is more reactive than benzene towards electrophilic substitution reaction. In the case of phenol, the intermediate carbocation is more resonance stabilised.
In a terrestrial ecosystem, detritus food chain is the major conduit for energy flow. Solar energy is the direct source for energy supply in a detritus food chain.
Histones are basic protein of major importance in packaging of eukaryotic $DNA. DNA$ and histone comprise chromatine forming bulk of eukaryotic chromosome. Histones are five major types $H_{l},\, H_{2}A,\, H_{2}B,\, H_{3}\, and\, H_{4}$.
HC $=$ C$^{-}$ is more stable than HC $=$ CH$^{-}$. HC $=$ C$^{-}$ has more s-character than HC $=$ CH$^{-}$.
$H_2Se$ is less acidic than $H_2S$. $S$ is less electronegative than $Se$.
$[Fe(H_2O)_5NO]SO_4$ is paramagnetic. The $Fe$ in $[Fe(H_2O)_5NO]SO_4$ has three unpaired electrons.
Diamond and graphite do not have the same crystal structure. Diamond is crystalline while graphite is amorphous.
$ClF_3$ has T-shape structure. It has two lone pairs arranged at 180$^{\circ}$ angle.
$BF_3$ molecule is planar but $NF_3$ is pyramidal. N atom is smaller than B.
AIDS is caused by the HIV, a retrovirus. Retroviruses have RNA genome.
Which of the following is not a peroxy acid?
Aspirin is known as :
Apiculture is associated with which of the following groups of plants?
Antiserum contain
An object $2.4\, m$ in front of a lens forms a sharp image on a film $12\, cm$ behind the lens. A glass plate $1\, cm$ thick, of refractive index $1.50$ is interposed between lens and film with its plane faces parallel to film. At what distance (from lens) should object shifted to be in sharp focus on film ?
An insect crawls up a hemispherical surface very slowly. The coefficient of friction between the insect and the surface is 1/3. If the line joining the centre of the hemispherical surface to the insect makes an angle a with the vertical, the maximum possible value of a so that the insect does not slip is given by