(b) Aluminium is more active than iron, yet there is less corrosion of aluminum when bot
are exposed to air.
(c) Solder is used for welding electrical wires together.
(d)A sulphide ore is converted into oxide to extract the metal for
(e)Tarnished copper vessels are cleaned with tamarind juice.
Answers
Answer:
b)Aluminium is indeed more reactive than iron yet there is less corrosion of aluminium as compared to iron , when both are exposed to air. This is because , when aluminium gets exposed to air , to form Al2O3 , it forms a protective layer, which protects the aluminium article from further corrosion .
c)Solder is an alloy of lead and tin ( Pb and Sn ) and has low melting point. Therefore it is used for welding electrical wires together. Solder is an alloy made up of lead and tin. it has very low melting point therefore it is used for welding electrical wires together.
d)A sulphide ore is converted into oxide ore by roasting. It is the process of heating the concentrated ore at a temperature not sufficient to melt the ore. The water content and the volatile impurities also get expelled. Zinc carbonate in its ore calamine (ZnCO3) is calcinated to obtain zinc oxide (ZnO).
e)The citric acid present in the lemon or tamarind neutralises the basis copper carbonate and dissolves the layer. That is why, tarnished copper vessels are cleaned with lemon or tamarind juice to give the surface of the copper vessel its characteristic lustre.