The green coating on copper status when exposed to atmosphere for a long time in due to the formation of
Copper hydroxide
Copper (II) carbonate
Copper (II) sulphate
Copper (II) oxide
The naturally occurring colourless crystalline form of aluminium oxide (Al2O3) is called
bauxite
limestone
quicklime
corundum
To reduce, Zinc oxide to Zinc, the material used is
Aluminium
Copper
Iron
Coke
The intensity of the flame colour of alkali metals can be measured using
spectrometer
mass spectrometer
galvanometer
flame photometer
An unreactive metal among the following
Magnesium
Gold
Sodium
The oxidiser in black gun powder is
Sodium nitrate
Sodium carbonate
Potassium nitrate
Potassium chloride
Group II metals are called
alkaline earth metals
alkali metals
transition metals
halogens
A grey- green gelatinous precipitate formed when iron salts is treated with alkali
Fe(OH)4
FeSO4
Fe(OH)2
FeCl3