Given below are two statements:
Statement I: In Lassaigne's test, the covalent organic molecules are transformed into ionic compounds.
Statement II: The sodium fusion extract of an organic compound having N and S gives prussian blue colour with $$FeSO_{4}$$ and $$Na_{4}[Fe(CN)_{6}]$$ In the light of the above statements, choose
the correct answer from the options given below.

Let us analyze both statements:

Statement I: In Lassaigne's test, the covalent organic molecules are transformed into ionic compounds.

In Lassaigne's test, the organic compound is fused with sodium metal. This converts covalent compounds containing N, S, or halogens into ionic compounds like NaCN, Na₂S, NaX (where X is halogen). This statement is true.

Statement II: The sodium fusion extract of an organic compound having N and S gives prussian blue colour with $$FeSO_4$$ and $$Na_4[Fe(CN)_6]$$.

When an organic compound contains both N and S, the fusion with sodium produces NaSCN (sodium thiocyanate) instead of NaCN and Na₂S separately. With $$FeSO_4$$, NaSCN would give a blood-red colour (ferric thiocyanate), not prussian blue.

For prussian blue test: $$Na_4[Fe(CN)_6]$$ reacts with $$Fe^{3+}$$ to give prussian blue $$Fe_4[Fe(CN)_6]_3$$. But in the presence of S, the CN⁻ ions are converted to SCN⁻, so prussian blue is not obtained directly. This statement is false.

Additionally, the reagent combination mentioned is incorrect. For the prussian blue test, we use $$FeSO_4$$ followed by $$FeCl_3$$, not $$Na_4[Fe(CN)_6]$$. Statement II is false.

The correct answer is Option 1: Statement I is true but Statement II is false.