When concentrated H2S04 spilts on the surface, it should be immediately cleaned :

When concentrated sulfuric acid (H2SO4) spills, it must be neutralized safely. Adding water (Option 2) is extremely dangerous because the dissolution of concentrated H2SO4 in water is highly exothermic [1]. Adding water to the acid can cause the solution to boil violently and spatter concentrated acid [t2]. Using a cloth (Option 1) is hazardous as concentrated acids can react with combustible materials or cause immediate tissue damage [t2]. The standard safety procedure involves neutralizing the spill with a base. Sodium carbonate (Na2CO3) is a highly effective and commonly used neutralizer for sulfuric acid spills [t1][t5]. It reacts with the acid to produce a salt (sodium sulfate), water, and carbon dioxide gas [t4]. Solid Na2CO3 is preferred as it neutralizes the acid without the risks associated with adding liquids to concentrated acid [t6]. Barium chloride (Option 4) is not used for neutralization as it is a salt, not a base.

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 2: Acids, Bases and Salts > Activity 2.10 > p. 24