4.3.2 Isotopes
1. Isotopes are atoms of certain elements which have the same number of protons but different number of neutrons in the nucleus of the atoms.
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2. Isotopes of the same element have same chemical properties. For example, both carbon-12 and carbon-13 burn in oxygen to form carbon dioxide.
3. Physical properties of isotopes are different. For example, carbon-14 isotope has a melting point, boiling point and density that are higher than those of carbon-12 and carbon-13.
Examples of isotopes
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