Ravi took iron fillings and sulphur powder in a flask in a ratio of 8 : 4 by mass and heat the flask. What will be left in the flask after heating?
Iron and sulphur form compound only when they are heated in their stoichiometric (relative quantity) ratio, i.e., 56:32 or 7:4. Here, iron is present more than the stoichiometric (relative quantity) ratio. Hence, iron sulphide and iron will be left after the reaction.