Online Chemistry Explorer

  Writing a Chemical Equation A chemical equation represents a chemical reaction. Word equations are a quick and simple way of summarising chemical reactions. For example, let’s consider the following description of this reaction: “Calcium carbonate powder reacts with a solution of dilute hydrochloric acid yields calcium chloride, liquid water and carbon dioxide gas.” This can be shown by the following word equation: Calcium carbonate + hydrochloric acid → calcium chloride + water + carbon dioxide   Another shorter way for representing chemical equations is to use chemical formulae instead of words. If you recall formulae of Calcium carbonate , hydrochloric acid , calcium chloride, water and carbon dioxide gas , the above word-equation can be written as Balanced Chemical Equations The law of conservation of mass states that mass can neither be created nor destroyed in a chemical reaction which means the total mass of the elements present in the products of a chemical ...

Reactions in Everyday Life Chemical reactions take place around us in many everyday situations. A flaky brown-coloured layer appearing on the surface of iron articles such as nail, crackers that render bright light and sound during festive season, digestion of food, milk left at room temperature during summers, Cooking of food and respiration are some examples for reactions happened in day-to-day life. In all the above situations, the nature and the identity of the initial substance have changed. So, i n a chemical reaction, at least one of the following changes will occur:  Change in state  Change in colour  Evolution of a gas  Change in temperature  Formation of a precipitate   What is a Chemical Reaction? A chemical reaction is a process in which the chemical structure of a substance changes, leading to the formation of a new substance with different properties. In other words, the reactants convert into products through the breaking and formation of chemica...