A reaction is a process in which substances undergo a chemical change, resulting in the formation of new substances with different properties.
There are several factors that can indicate whether or not a reaction will occur, such as the reactants involved, temperature, and presence of a catalyst.
Some common signs of a chemical reaction include changes in color, formation of a gas or bubbles, and the release or absorption of energy.
Some reactions can be reversed by applying certain conditions, such as changing the temperature or adding a catalyst. However, some reactions are irreversible and cannot be undone.
The strength of a reaction depends on the nature of the substances involved, their concentrations, and the conditions under which the reaction takes place. Some substances may have a higher reactivity due to their chemical properties, making them more likely to undergo a reaction.