Let's look at a few assessment scenarios. Try to determine what type of assessment is being used, formal or informal. 1  Example 1. 2  A kindergarten teacher sets aside the first 15 minutes of every day to allow students to explore, play or engage in any activity of their choice.
Chemical bonds are made or broken in order to create a new molecule. One example of a chemical reaction is the rusting of a steel garbage can. That rusting happens because the iron (Fe) in the metal combines with oxygen (O2) in the atmosphere. Chemical bonds are created and destroyed to finally make iron oxide (Fe2O3).
A chemical change (that is, a chemical reaction) is one in which the organization of the atoms is altered. An example of a chemical reaction is the burning of methane in the presence of molecular oxygen (O 2) to form carbon dioxide (CO 2) and water.