1.The mineral containing both magnesium and calcium is
magnesite
calcite
carnallite
dolomite
2.The most extensive, commercially useful source of thorium as monazite sand occurs in India at
Orissa coast
Travancore coast
West Bengal coast
Gujarat coast
3.The main active constituent of tea and coffee is
nicotine
chlorophyll
caffeine
aspirin
4.The hardest form of carbon is
coke
graphite
diamond
charcoal
5.The hottest part of the gas flame is known as
luminous zone
dark zone
blue zone
non-luminous zone