What are 2 things that we call a molecule before and after a chemical reaction

The substances used in the beginning of a chemical reaction are called the reactants and the substances found at the end of the reaction are known as the products.

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Urban growth invariably feeds increased commercialization and industrialization. it requires continually expanding land areas. when urbanization rates are high, and countries do not have the institutional and managerial capacities or economic wherewithal to manage such rapid growths, they exert intense pressure on the types and nature of the resulting settlements. they contribute to the development of overcrowded slums and shanty towns without adequate essential services and necessary infrastructure.-by asit k. biswas and cecilia tortajada