$$\mathrm{K_2Cr_2O_7}$$ paper acidified with dilute $$\mathrm{H_2SO_4}$$ turns green when exposed to :

Which of the Phosphorus oxoacid can create silver mirror from $$\mathrm{AgNO_3}$$ solution?

In liquation process used for tin (Sn), the metal :

Given below are two statements.

Statement I : Stannane is an example of a molecular hydride.

Statement II : Stannane is a planar molecule.

In the light of the above statement, choose the most appropriate answer from the options given below.