Oxides of certain non-metals like carbon, sulphur and phosphorous dissolve in water to form the corresponding
acids
hydrogen
alkalies
oxygen
Which is a disinfectant often used in homes for killing germs?
chlorine
potassium permanganate
potassium chromite
sulfuric acid
Bicarbonates of calcium and magnesium causes
temporary hardness
permanent hardness
temporary softness
permanant softness
_____________causes Leucoderma, skin cancer.
Nickel
Chromium
Cadmium
Uranium
Iron is mixed with small amounts of nickel and chromium to form an alloy is called
alloying
tin plating
electroplating
galvanising
______________occurs when heated water enters a river or stream.
Air pollution
Thermal pollution
Soil pollution
Nuclear pollutants
The pressure of impurities makes the freezing point of a liquid
increases
not affect
decreases
increases rapidly
Which is used in photosynthesis?
water
carbon monoxide
________________is inflammable.
Carbondioxide
Carbon monoxide
Hydrogen
Argon
Which is used for protecting metallic tools and machine parts?
Grease
coaltar
oil paints
enamel coating
