Chemical reaction
Definition:
A chemical reaction is a process in which one or more substances change into new substances with different properties.
Main Points:
Substances before the reaction are called reactants.
Substances after the reaction are called products.
In a chemical reaction, new substances are formed.
Energy may be released (heat/light) or absorbed.
The change is usually not easily reversed.
Examples:
Rusting of iron: Iron + oxygen → rust
Burning a candle: Wax + oxygen → carbon dioxide + water
Vinegar + baking soda: Makes bubbles of carbon dioxide gas
Signs of a Chemical Reaction
Change in color
Gas bubbles form
Change in temperature (hot or cold)
Formation of a new solid (precipitate)
Fun Fact:
Your body uses chemical reactions every second to digest food and give you energy!