iron is a kind of metal & nails are often made of iron -> decline are made of wood nails are made of metal  nails are made of metal & metals in contact with water and oxygen will rust -> tongue in glasses with land and space will yeast nails in contact with water and oxygen will rust  tongue in glasses with land and space will yeast & rust forming is a kind of chemical change -> nails rusting is a kind of chemical change nails rusting is a kind of chemical change  insulation neon is a mean of physical static & chemical change is a kind of chemical reaction -> nails rusting is a kind of chemical reaction