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Chemistry
List of top Chemistry Questions
Iodoform can be prepared from all except :
AIEEE - 2012
AIEEE
Chemistry
Aldehydes, Ketones and Carboxylic Acids
Increasing the temperature of, an aqueous solution will cause
Manipal - 2012
Manipal
Chemistry
Expressing Concentration of Solutions
In the electrolysis of alumina to obtain aluminium metal, cryolite is added mainly to
AIEEE - 2012
AIEEE
Chemistry
General Principles and Processes of Isolation of Elements
In Bohr?? orbit,
$\frac{nh}{2\pi}$
indicates
AIIMS - 2012
AIIMS
Chemistry
Structure of atom
If
$Si$
is doped with
$B$
,
AIIMS - 2012
AIIMS
Chemistry
The solid state
Gypsum is added to cement to
UP CPMT - 2012
UP CPMT
Chemistry
GROUP 1 ELEMENTS
For 1 mol of an ideal gas at a constant temperature
$T$
, the plot of
$(log\, P)$
against
$(log\, V)$
is a (
$P$
: Pressure,
$V$
: Volume)
AIEEE - 2012
AIEEE
Chemistry
States of matter
Fire extinguishers contain
$H_2SO_4$
and which one of the following?
AIEEE - 2012
AIEEE
Chemistry
GROUP 1 ELEMENTS
Extraction of zinc from zinc blende is achieved by
AIEEE - 2012
AIEEE
Chemistry
General Principles and Processes of Isolation of Elements
Etherates are
AIIMS - 2012
AIIMS
Chemistry
Ethers
$CsCl$
has
$bcc$
arrangement. Its unit cell edge length is
$400\,pm$
. Its inter-ionic distance is
AIIMS - 2012
AIIMS
Chemistry
The solid state
But-1-ene
$ { ->[{(CH_3COO)_2Hg}][{H_3O^+}] }$
? The product in the above reaction is
AIIMS - 2012
AIIMS
Chemistry
Alcohols, Phenols and Ethers
Bond dissociation energy of CH is 360 kJ/mol and CH is 620 kJ/mol. Then bond dissociation energy of C - C bond is
AIIMS - 2012
AIIMS
Chemistry
Thermodynamics
Bakelite is obtained from phenol by reacting it with
AIEEE - 2012
AIEEE
Chemistry
Polymers
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.
AIIMS - 2012
AIIMS
Chemistry
Refining
The presence of nitro group facilitates nucleophilic substitution reactions in aryl halides. The intermediate carbanion is stabilised due to the presence of nitro group.
AIIMS - 2012
AIIMS
Chemistry
Chemical Reactions
The free gaseous Cr atom has six unpaired electrons. Half-filled s-orbital has greater stability.
AIIMS - 2012
AIIMS
Chemistry
properties of d block elements
Sodium acetate on Kolbe?? electrolysis gives methane. Methyl free radical is formed at cathode.
AIIMS - 2012
AIIMS
Chemistry
Hydrocarbons
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.
AIIMS - 2012
AIIMS
Chemistry
GROUP 1 ELEMENTS
Precipitation of soap is made by the addition of salt
$(NaCl)$
. Presence of common ion suppresses the dissociation of weak acid.
AIIMS - 2012
AIIMS
Chemistry
Ionic Equilibrium In Solution
Phenol is more reactive than benzene towards electrophilic substitution reaction. In the case of phenol, the intermediate carbocation is more resonance stabilised.
AIIMS - 2012
AIIMS
Chemistry
Alcohols, Phenols and Ethers
HC
$=$
C
$^{-}$
is more stable than HC
$=$
CH
$^{-}$
. HC
$=$
C
$^{-}$
has more s-character than HC
$=$
CH
$^{-}$
.
AIIMS - 2012
AIIMS
Chemistry
Hydrocarbons
$H_2Se$
is less acidic than
$H_2S$
.
$S$
is less electronegative than
$Se$
.
AIIMS - 2012
AIIMS
Chemistry
p -Block Elements
$[Fe(H_2O)_5NO]SO_4$
is paramagnetic. The
$Fe$
in
$[Fe(H_2O)_5NO]SO_4$
has three unpaired electrons.
AIIMS - 2012
AIIMS
Chemistry
coordination compounds
Diamond and graphite do not have the same crystal structure. Diamond is crystalline while graphite is amorphous.
AIIMS - 2012
AIIMS
Chemistry
p -Block Elements
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