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What are Isotopes?. Isotopes are atoms of the same element that have the same number of protons , but different number of neutrons . This results in different atomic mass. Properties of Isotopes. Each element has a certain number of isotopes that occur naturally.
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What are Isotopes? Isotopes are atoms of the same element that have the same number of protons, but different number of neutrons. This results in different atomic mass.
Properties of Isotopes Each element has a certain number of isotopes that occur naturally. For example, Carbon-12, Carbon-13, and Carbon 14. The mass number for each is the sum of protons and neutrons, so C-13 has an extra neutron, and C-14 has 2 extra. Isotopes of an element share most of the same physical and chemical properties. Except…
Radioactive Isotopes • Radioactive isotopes have an unstable nucleus, meaning they decay (fall apart) over a certain amount of time. As they decay, they give off smaller particles and energy. Why is this important?
Radiometric Dating A technique used to date fossils and rock. Measures the amount of a certain isotope that remains compared to the amount that has decayed. Since the rate of decay for every isotope is constant it is possible to predict the age of the sample.
Common dating methods Potassium-Argon dating: Potassium decays to Argon with a half life of 1.3 billion years. Applies to the earth’s oldest rocks. Compares ratio of potassium isotope to argon to determine approximate age within a couple million years.
Radiocarbon dating: used to estimate age of organic remains. Carbon-14 isotope decays with a half life of only 5730 years. Compares ratio of normal C-14 in atmosphere to C-14 remains in organic remains.