In this lesson, we will learn:
- How to determine whether a chemical reaction has occurred.
- The methods of writing a chemical reaction.
- Chemical reactions involve collisions between molecules – they are far too small to see directly with the naked eye. Instead we make observations which are evidence that a reaction has happened or is happening.
- For chemists, an observation is a change that can be measured we can tell directly using our senses, for example seeing a color change, feeling a temperature change (like a glass beaker warming up) or seeing gas being released from a test tube.
- The reason this happens is because different chemical compounds have different properties that we can see when that chemical is produced. For example a color change from brown to colorless might mean a reactant chemical that is brown is being converted into a product that is colorless.
- There are two ways to write that a reaction is taking place:
- a word equation
- a chemical (symbol) equation.
- The → arrow found in a chemical equation is very important; it shows that a reaction is taking place. The reactants (what gets put in) of a reaction are always on the left-hand side of it, and the products (the new chemical that gets made) of a reaction are always on the right-hand side.