Megan left her bicycle outside on the patio while she went on vacation for several weeks. when she returned, megan discovered a reddish substance, rust, on the handlebars of her bicycle. the rust is an example of a(n)

 rusting of iron is a chemical change because it is two substances reacting together to make a new substance. When iron rusts, iron molecules react with oxygen molecules to make a compound called iron oxide. Rusting would only be a physical change if iron molecules remained pure iron throughout the process.

this protocol provides a detailed procedure for total protein extraction for western blot analysis from achieved samples following trizol isolation of rna.