When one strikes a safety match, the first step is:
burning of sulphur
decomposition of potassium chlorate into potassium chloride and oxygen
conversion of a small amount of red phosphorus into white phosphorus
burning of glue and starch
The LPG cooking gas contains propane and butane as the constituents. A sulphur containing compound is added to the LPG, because:
it lowers the cost of production
it enhances the efficiency of LPG
it facilitates easy detection of leakage of the gas
it assists in liquefying hydrocarbons
C.
it facilitates easy detection of leakage of the gas
LPG is prepared by refining petroleum or 'wet' natural gas, and is almost entirely derived from fossil fuel sources, being manufactured during the refining of petroleum (crude oil), or extracted from petroleum or natural gas streams as they emerge from the ground.
Match List-I with List-II
List I (Element)
List II (Highest Valency)
(a) - 2, (b) - 4, (c) - 1, (d) - 3
(a) - 2, (b) - 1, (c) - 4, (d) - 3
(a) - 3, (b) - 1, (c) - 4, (d) - 2
(a) - 3, (b) - 4, (c) - 1, (d) - 2
Combination of one volume of nitrogen with three volumes of hydrogen produces
one volume of ammonia
two volumes of ammonia
three volumes of ammonia
one and a half volumes of ammonia
The setting time of cement is lowered by adding:
oxides of aluminium
gypsum
oxides of magnesium
silica
Emulsion is known as a:
colloidal solution of substances having different physical states
true solution
distillation mixture for making alcohols
colloidal solution of two liquids
If one mixes up ashes with animal fat, the substance received in the crude form is called:
Pheromone
Soap
Cement
Concrete
Which one of the following gases gives acidic solution on dissolving in water?
Hydrogen
Carbon dioxide
Nitrogen
Oxygen
How many moles of hydrogen atom are present in one mole of Aluminium hydroxide?
One mole
Two moles
Three moles
Four moles