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Useful chemicals from crude oil

Rearrangement of atoms

In a chemical reaction, the substances that react together are called the reactants, while the substances that are formed are called the products.

reactants → products

The products have different properties from the reactants.

As a chemical reaction takes place, atoms in the reactants are rearranged to make the products. The number of atoms of each element in the reactants is the same in the products. No atoms are added or taken away. This is called the conservation of atoms.

When polythene is made from ethene, the polymer has the same number of carbon and hydrogen atoms as the ethene molecules it is made from.

Ethene makes polyethene

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