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).
Chemical reactions involve rearrangement of the atoms and produce. new substances in this process. For example, in the above picture, just the mixing of two substances can cause. the chemical reaction to occur. Chemical Reactions are everywhere in nature. The process by which the plants make their own food is called photosynthesis.