Total pressure exerted by a mistress of two or more than two gases in a definite volume as any given temperature is equal to the sum of partial pressures which each gas would exert, if it occupied the same volume alone, at the same temperature This is a statement.
A boy accidently splashes a few drops of conc. H2SO4 on his cotton shirt. A few minutes later, the splashed part blacken and holes appear.This is because the sulphuric acid.