Examples of Isotopes and their Subatomic Composition

🧪 Quick Study Guide

• ⚛️ Isotopes are variants of a chemical element which have the same number of protons and electrons, and therefore the same chemical properties, but different numbers of neutrons.
• ⚖️ The number of protons defines the element, while the number of neutrons determines the isotope.
• ☢️ Isotopes can be stable or radioactive. Radioactive isotopes undergo radioactive decay.
• 🔢 Isotope notation: $_{Z}^{A}X$, where $X$ is the element symbol, $Z$ is the atomic number (number of protons), and $A$ is the mass number (number of protons + neutrons).
• 🗓️ Half-life: The time it takes for half of the radioactive isotopes in a sample to decay.
• 💡 Applications of isotopes: Carbon dating, medical imaging, cancer treatment, and industrial applications.

Practice Quiz

1. Which of the following statements best describes isotopes?
   1. Atoms with the same number of neutrons but different numbers of protons.
   2. Atoms with the same number of protons but different numbers of neutrons.
   3. Atoms with different numbers of protons and electrons.
   4. Atoms with the same number of electrons but different numbers of protons.
2. What is the mass number of an isotope?
   1. The number of protons in the nucleus.
   2. The number of neutrons in the nucleus.
   3. The sum of protons and neutrons in the nucleus.
   4. The sum of protons, neutrons, and electrons in the atom.
3. Which isotope is commonly used in carbon dating?
   1. Carbon-12
   2. Carbon-13
   3. Carbon-14
   4. Carbon-15
4. What distinguishes radioactive isotopes from stable isotopes?
   1. Radioactive isotopes have more protons.
   2. Radioactive isotopes undergo radioactive decay.
   3. Radioactive isotopes have fewer neutrons.
   4. Radioactive isotopes do not contain electrons.
5. Which of the following is a medical application of isotopes?
   1. Producing electricity in nuclear power plants.
   2. Determining the age of rocks.
   3. Medical imaging and cancer treatment.
   4. Manufacturing fertilizers.
6. What is the role of neutrons in isotopes of the same element?
   1. Neutrons determine the chemical properties of the isotope.
   2. Neutrons determine the atomic number of the isotope.
   3. Neutrons affect the mass and stability of the isotope.
   4. Neutrons have no effect on the properties of the isotope.
7. If an isotope has an atomic number of 6 and a mass number of 14, how many neutrons does it have?
   1. 6
   2. 8
   3. 14
   4. 20