Question

1. what elements did the curies discover? 5. explain what an electroscope does and how it works. 6. name a material that makes a good shield against radiation.

Explanation:

1. The Curies, Marie and Pierre Curie, discovered radium and polonium. They conducted extensive research on radioactive substances.
2. An electroscope is a device used to detect the presence of electric charge. It works based on the principle of electrostatic induction. When a charged object is brought near the electroscope, the leaves of the electroscope diverge due to the repulsion of like - charges.
3. Lead is a well - known material that makes a good shield against radiation. Its high density and atomic number make it effective at absorbing and blocking radiation.

Answer:

1. Radium and polonium
2. An electroscope detects electric charge. It works by electrostatic induction causing leaf divergence.
3. Lead