Three states of matter -- What is a solid? -- What is a liquid? -- What is a gas? -- The air we breathe -- The water cycle -- The water cycle: around and around -- Heating, melting, cooling, and freezing -- Does it dissolve? -- Can salty seawater become a solid? -- Mixed-up mixtures -- No going back! -- Melting metals for recycling.
"Why do we burp when we take a swig of soda? What are air and water actually made of? And when a liquid raw egg becomes a solid fried egg, can this change of state ever be reversible? Packed with hands-on investigations, this book explores topics including the properties of solids, liquids, and gases; how liquids become solids and how solids become liquids; how the water cycle works; why seawater is salty; and how changing states make recycling possible." --