FIRST, classify the following as a pure substance and mixture (add this classification in the first gap). THEN, add the labels "element", "compound", "homogenous" and "heterogenous" to the second gap. rain Mercury clean air steel Methane (CH4) Label the following properties as either chemical or physical properties: An apple can be metabolised in your body Food will rot if left out for too long Iron is solid at room temperature Silver can tarnish over time when exposed to air This laptop screen is 14 long