A.   Silica is soluble in water

        B.   Silica is soluble in acids except hydrofluoric acid

        C.   Hydrolysis of silicon tetrachloride gives silicic acid

        D.   When passed in water, SiF4 is hydrolysed to give soluble H2SiF6

        A.   As we move down the group upto silicon, effective nuclear charge outbalances the effect of additional shell leading to a sharp increase and afterwards gradual increase in size

        B.   As we move down the group after silicon, effective nuclear charge outbalances the effect of additional shell leading to only a marginal increase in size

        C.   As we move down the group upto silicon, the effect of additional shell leads to a sharp increase in size, subsequently it becomes easy for electron loss, leading to gradual increase in size

        D.   As we move down the group after silicon, reduction takes effect as against oxidation leading to gradual increase in size

        A.   +4 and+6

        B.   +4

        C.   +2 and +4

        D.   +1 and +4

        A.   Very large amount of energy is required to form a M4+ ion

        B.   The ionisation energies required to form the M4+ is low

        C.   Bond dissociation energy of group 4 elements is high

        D.   The energy needed to attain the activated complex is high

        A.   Carbon black

        B.   Silicates

        C.   Lead

        D.   Carbon IV oxide

        A.   Graphite

        B.   Coke

        C.   Lead

        D.   Carbon black

        A.   Lead

        B.   Diamond

        C.   Graphite

        D.   Tin

        A.   Reduction of oxides of tin with carbon

        B.   Oxidation of oxides of tin with carbon

        C.   Reduction of oxides of tin with hydrogen

        D.   Oxidation of oxides of tin with iron

        A.   Subjecting carbon to high temperature and pressure

        B.   Subjecting silicon to high temperature and pressure

        C.   By boiling and quick quenching of carbon, silicon and germanium

        D.   By boiling and quick quenching of carbon and silicon

        A.   The oxidation of germanium dioxide with copper

        B.   Reduction of germanium dioxide with tin

        C.   Reduction of germanium dioxide with carbon or hydrogen

        D.   Oxidation of germanium dioxide with mercury

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