Explain
Fe produces `H_2` with dil HCl but Cu does not.

Explain why 1-butyne reacts with ammoniacal silver nitrate to produce a white precipitate, but 2-butyne does not.

Explain with reason the following: Cu^+ ion does not form coloured salts like Cu^(2+) ion.

Explain why 1-butyne produces white precipitate with ammoniacal AgNO_3 solution but 2 butyne does not respond to this reaction.

A molecule of H_(2) exist while that of the He_(2) does not. Explain.

5.5 g of a pure sample of FeS reacts with dil. H_(2)SO_4 . H_(2)S gas so produced is then completely burnt in air. Find the volume of SO_(2) thus obtained, measured at 25^(@)C and 750 mm pressure of Hg.

Of the elements Zn , Mg Cu and Ag , which are able to produce H_(2) gas when they are treated with dilute HCl solutions ? [ Given E_(Zn^(2+)|Zn)^(@)= -0.76 V , E_(Mg^(2+)|Mg)^(@) = - 1.20 V, E_(Cu^(2)+|Cu)^(@)+0.34 V and E_(Ag^(+)|Ag)^(@) = + 0.80 V ]

A bone kept in dil HCl for three days shall

Explain the polarity of covalent bonds in H_(2)O and HCl.

Explain why concentrated HCL is not used in the laboratory preparation of H_(2) gas.