There are two overarching types of assessment in educational settings: informal and formal assessments. Both types are useful when used in appropriate situations. Informal assessments are those assessments that result from teachers' spontaneous day-to-day observations of how students behave and perform in class.
In the chemical industry it is used to heat reactants and in processes such as distillation, product drying, electrolysis, and treatment of waste. At present, the energy used still relies mainly on fossil fuels, but even so the use of these can be reduced in several ways (Table 2).
Share. A synthesis reaction or direct combination reaction is one of the most common types of chemical reactions. In a synthesis reaction two or more chemical species combine to form a more complex product. By Anne Marie Helmenstine, Ph.D. A + B â AB. The combination of iron and sulfur to form iron (II) sulfide is an example of a synthesis reaction :