Step 1: Identify X and Y:
The dehydration of carboxylic acids with conc. \(\text{H}_2\text{SO}_4\) is a specific reaction.
Formic acid (\(\text{HCOOH}\)) undergoes dehydration to give Carbon Monoxide (\(\text{CO}\)) and water.
Reaction: \(\text{HCOOH} \xrightarrow{\text{conc. H}_2\text{SO}_4, \Delta} \text{CO} \uparrow + \text{H}_2\text{O}\).
So, Acid X = Formic Acid, Gas Y = Carbon Monoxide (\(\text{CO}\)).
Step 2: Determine Hybridisation of C in CO:
The Lewis structure of CO is \(:\text{C} \equiv \text{O}:\).
The carbon atom forms a triple bond (1 sigma + 2 pi) and has one lone pair.
Steric number = (Number of sigma bonds) + (Lone pairs) = \(1 + 1 = 2\).
Steric number 2 corresponds to \(sp\) hybridisation.
Step 3: Determine Nature of Y (CO):
Carbon monoxide (\(\text{CO}\)) is a well-known neutral oxide (along with \(\text{N}_2\text{O}\) and \(\text{NO}\)). It does not react with acids or bases to form salts.
Conclusion:
Hybridisation is \(sp\) and nature is Neutral.
Final Answer:
Option (B).