Colour change is an obvious sign of a reaction occurring.
Other indications include:
The balanced chemical equation for a reaction tells the story of a chemical reaction by showing the reactants that are consumed and the products that are formed. It also provides information on the stoichiometry of the reaction, including the ratios of reactants and products involved.
My Chemistry lecturer tells me that the combustion of Hydrogen and Oxygen into water is the fastest chemical reaction.
because it can't be changed back into it's normal form. the smell changes, which also tells you when a chemical change is taking place.
A subscript
A chemical equation
Products. Products ----> Reactants.
It tells how much the reaction rate is affected by concentrations.
The formula of a chemical equation tells you the type and number of atoms or molecules involved in a chemical reaction. It helps to balance the equation to ensure that mass is conserved and the reaction follows the law of conservation of mass.
It tells you the number of molecules or number of moles of each substance.
It is one way of representing a chemical reaction: it tells you what reacts and what is produced. Word equations are an efficient way to describe chemical changes, to help chemists recognize patterns, and to predict the products of a chemical reaction.
The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction. This means that the total mass of the reactants before a chemical reaction is equal to the total mass of the products after the reaction. In other words, the mass of the reactants is the same as the mass of the products in a chemical reaction.
I think that a chemical equation tells a chemist that substances you start with and substances you end with