Essential constituent of an amalgam is
Iron
An alkali metal
Silver
Mercury
Which of the following is used as white pigment
To obtain steel entirely free from sulphur and phosphorus, the process used is
The aqueous solution containing which one of the following ions will be colourless
How many unpaired electrons are there in $N{i^{2 + }}$
The element the usually does $NOT$ show variable oxidation states is