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).
Chemical Reactions (Also known as a Chemical Change). A chemical reactions occurs when two or more substances meet, and they react in a way the either causes a change in the original substances, or the creations of one or two entirely new substances. A commonly known example is when vinegar and baking soda are mixed together. Vinegar is an acid, and baking soda is a base.