In the lime kiln, the reaction CaCO3(s) → CaO(s) + CO2 (g) goes to completion because:
of high temperature
CaO is more stable than CaCO3
CO2 escapes simultaneously
CO2 is a gaseous product
The rate of a reaction is doubled for every 10° rise in temperature. The increase in reaction rate as a result of temperature rise from 10° to 100° is :
112
512
400
614
When a beam of light is passed through a colloidal solution it :
is reflected
is scattered
transmitted
absorbed
B.
is scattered
When a beam of light is passed through a colloidal solution it is scattered.
The electron affinity values for the halogens show the following trend :
F < Cl > Br >I
F < Cl< Br< I
F > Cl > Br > I
F < Cl > Br < I
When H2S gas is passed through nitric acid, the product is:
prismatic S (colloidal)
amorphous S
monoclinic S
plastic S
Atoms in a P4 molecule of white phosphorus are arranged regularly in space in which of the following way ?
At the comers of tetrahedron
At the comers of a cube
At the comers of a four membered ring
At the centre and comers of a equivalent triangle
The catalytic activity of the transition metals and their compounds is described to :
their chemical reactivity
their magnetic behaviour
their unfilled d-orbitals
their ability to adopt multiple oxidation states and their complexing ability
The compound ZnFe2O4 is:
a normal spinel compound
a inverse spinel compound
interstitial compound
covalent compound
High purity Si and Ge for semiconductor properties can be obtained by :
calcination
roasting
zone refining
thermic process
Name of the alloy of aluminium which is used in aeroplane is :
duralumin
bell metal
aluminium bronze
alumina