whooping cough
tetanus
diphtheria
All the three
brass
common salt
cane sugar
water
Astatine
Francium
Tritium
Zirconium
iron with very low percentage of carbon
iron with high percentage of carbon
iron and chromium
iron and manganese
homogeneous, sulphates
heterogeneous, nitrates
heterogeneous, carbonates
homogeneous, silicates
gypsum
urea
potassium nitrate
ammonium phosphate
quicklime
gypsum
soda lime
bleaching powder
the percentage of carbon dioxide in air is kept almost constant
air always contains a constant proportion of oxygen
sufficient amounts of carbohydrates are produced
the process of photosynthesis proceeds smoothly
coal gas
producer gas
water gas
gobar gas
Rutherford
Moseley
Niels Bohr
J.J. Thomson
Wohler
Dalton
Lavoisier
Fischer
they may appear better
they can resist the action of acids and alkalies
they lose their brittleness
they can withstand temperature shocks
sublimation
oxidation
reduction
decomposition
Distillation of water
Action of heat on potassium chlorate
Powdering of glass
Burning of an electric lamp
C6H12O6
C2H5OH
C12H22O11
C7H8O
an oxidation process
a reduction process
a physical change
an electro-chemical process
acetone
ether
acetic acid
methyl salicylate
copper sulphate and water
copper sulphate, lime and water
thio-urea and lime
copper sulphate and thio-urea
ethyl alcohol
methyl alcohol
carbon monoxide
carbon dioxide
a basic salt
an acid salt
a double salt
a normal salt
it becomes coloured
it gets evaporated in air
it gets oxidised to phosgene
it gets decomposed to chloropicrin
lead
chromium
zinc
tin
Aluminium
Copper
Zinc
Iron
a deliquescent substance
an efflorescent substance
a hygroscopic substance
a dehydrating substance
Kerosene oil
Diesel oil
Lubricating oil
Petroleum ether
Aluminium
Chromium
Nickel
Tungsten
nitrates
nitrites
hyponitrates
nitrides
a very sweet smell
a very pungent smell
an irritating smell
no smell at all
dichloro-phenoxy-acetic acid
superphosphate of lime
chlorofluorocarbons (CFC)
dichloro-diphenyl-trichloro-ethane
galena
dolomite
sylvine
pitchblende