Learn: Isotopes and Why They Exist

Welcome!Welcome to your lesson on isotopes. You’ve already learned about the structure of atoms and the difference between atomic number and mass number. Let’s build on that by exploring isotopes and why they exist.

What Are Isotopes?Isotopes are atoms of the same element with the same number of protons but different numbers of neutrons. This means they have the same atomic number but different mass numbers. Isotopes are important because they can have different physical properties and uses.

Why Do Isotopes Exist?Isotopes exist because the number of neutrons in an atom can vary without affecting the atom’s identity as an element. This variation happens naturally and allows for different forms of the same element. For example, carbon has isotopes like carbon-12 and carbon-14.

Examples of IsotopesLet’s consider carbon isotopes. Carbon-12 has 6 protons and 6 neutrons, while carbon-14 has 6 protons and 8 neutrons. Both are forms of carbon, but carbon-14 is radioactive and used in carbon dating.

Why Are Isotopes Useful?Isotopes have many practical applications. For example, radioactive isotopes like uranium-235 are used in nuclear power generation, while stable isotopes like oxygen-18 are used in climate studies to analyse ice cores.

Review Time!Great work! You’ve learned about isotopes, their structure, why they exist, and their applications. Let’s test your understanding with a few final questions.