Chemistry
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Atoms and chemical reactions
Chemical transformation
A chemical transformation is a process during which some substances disappear and new substances are formed.
A chemical transformation can be described by a simple word equation:
- Substances which are consumed during a chemical transformation are called reactants.
- Substances that are formed in a chemical transformation are called products.
Example: the combustion of carbon.
Carbon and dioxygen disappear therefore they are reactants.
Carbon dioxide is formed therefore it is a product.
Simple word equation for the combustion of carbon;
Carbon + Dioxygen → Carbon dioxide
Reactants Products
General rules for writing a simple word equation:
- The names of reactants are indicated on the left and separated by a + sign.
- The names of products are indicated on the right separated by a + sign.
- The names of those reagents and products are separated by an arrow.
Comment: the + sign means "reacts with" and arrow "to give". Then simpe word equation should be read: "Carbon and dioxygen react to give carbon dioxide".
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