Why is radium stored in lead containers?

Radium is a radioactive element that emits harmful radiation, which can pose significant health risks. Storing radium in lead containers is primarily due to lead's effectiveness as a radiation shield. Lead has a high atomic number, which makes it particularly good at preventing the penetration of different types of radiation, including gamma rays and X-rays that radium emits.

By storing radium in lead containers, the harmful radiation is significantly absorbed by the lead, reducing exposure to people and the environment. This property of lead is crucial in ensuring safety in handling radioactive materials, making it a standard practice in the storage of radium and other radioactive substances. Therefore, the main reason for using lead containers is its ability to protect against the harmful effects of radiation emitted by radium.