227
          
        
        
          
            Freezing
          
        
        
          Icicles are spikes of ice
        
        
          that form when dripping
        
        
          water freezes. You often
        
        
          see them on trees in
        
        
          winter. If water keeps
        
        
          dripping down and
        
        
          freezing, the icicle will
        
        
          get longer and longer.
        
        
          
            Changing states
          
        
        
          
            Melting
          
        
        
          
            chocolate
          
        
        
          Because the warmth of your mouth makes it melt.
        
        
          
            Melting
          
        
        
          When you don’t eat your
        
        
          ice cream quickly enough,
        
        
          it melts and changes from a
        
        
          solid to a liquid! Chocolate
        
        
          melts too, and makes
        
        
          your hands all sticky.
        
        
          Most solids will melt if the
        
        
          temperature is high enough.
        
        
          
            Evaporating
          
        
        
          In the open air, water slowly turns into
        
        
          vapour – this is called evaporation.
        
        
          Wet clothes dry on a line because the
        
        
          water they hold evaporates.
        
        
          Washing dries faster on a hot day,
        
        
          when heat turns water into vapour
        
        
          very quickly.
        
        
          M
        
        
          m
        
        
          m
        
        
          m
        
        
          .
        
        
          .
        
        
          .
        
        
          f
        
        
          r
        
        
          o
        
        
          z
        
        
          e
        
        
          n
        
        
          f
        
        
          r
        
        
          u
        
        
          i
        
        
          t
        
        
          i
        
        
          n
        
        
          s
        
        
          i
        
        
          d
        
        
          e
        
        
          
            Become
          
        
        
          
            an expert...
          
        
        
          
            230-231
          
        
        
          Molecules
        
        
          
            232-233
          
        
        
          Reactions
        
        
          and changes