Related Questions

Conversion of yellow phosphorous to red phosphorous is done by heating it in covered retorts at __________ °C in absence of air.
A 50-80
B 250-400
C 1000-1200
D 800-900
The most reactive allotropic form of phosphorus is __________ phosphorus.
A Red
B Yellow
C Violet
D Black
Red phosphorous is changed into white phosphorous by
A Heating in presence of light
B Melting under pressure
C Vaporisation followed by condensation
D None of these
Both white phosphorous as well as red phosphorous
A Are soluble in CS2
B Burns when heated in air
C Reacts with hot caustic soda solution to give phosphine
D All of the above
. Diamond is an allotropic form of
A germanium
B carbon
C silicon
D sulphur
Heat evolved/absorbed during conversion of a substance from one allotropic form to another is termed as the heat of
A Fusion
B Vaporisation
C Transition
D None of these
Absorption/evolution of heat during conversion of a substance from one allotropic form to another is termed as the heat of
A Sublimation
B Fusion
C Transition
D Vaporisation
For the allotropic forms of iron, the points of arrest are
A The points where no further change occurs
B Constant for all metals
C The points where there is no further flow of metal
D The points of discontinuity
A material is said to be allotropic, if it has
A Fixed structure at all temperatures
B Atoms distributed in random pattern
C Different crystal structures at different temperatures
D Any one of the above
A material is known as allotropic or polymorphic if it
A Has a fixed structure under all conditions
B Exists in several crystal forms at different temperatures
C Responds to heat treatment
D Has its atoms distributed in a random pattern

Next steps